Percutaneous spinal implants and methods

ABSTRACT

An apparatus includes an elongate member including a cutting edge disposed at a distal end portion of the elongate member. The cutting edge is configured to cut a portion of an implant when the elongate member moves relative to the implant.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and is a continuation-in-part ofU.S. patent application Ser. No. 11/454,153, entitled “Apparatus andMethod for Treatment of Spinal Conditions,” filed Jun. 16, 2006, whichis a continuation-in-part of International Patent Application No.PCT/US2006/005580, entitled “Percutaneous Spinal Implants and Methods,”filed Feb. 17, 2006, and which is a continuation-in-part of U.S. patentapplication Ser. No. 11/059,526, entitled “Apparatus and Method forTreatment of Spinal Conditions,” filed Feb. 17, 2005 now abandoned, andwhich is a continuation-in-part of U.S. patent application Ser. No.11/252,879, entitled “Percutaneous Spinal Implants and Methods,” filedOct. 19, 2005, which claims priority to U.S. Provisional ApplicationSer. No. 60/695,836, entitled “Percutaneous Spinal Implants andMethods,” filed Jul. 1, 2005, and which is a continuation-in-part ofU.S. patent application Ser. No. 11/252,880, entitled “PercutaneousSpinal Implants and Methods,” filed Oct. 19, 2005 now abandoned, whichclaims priority to U.S. Provisional Application Ser. No. 60/695,836,entitled “Percutaneous Spinal Implants and Methods,” filed Jul. 1, 2005;each of which is incorporated herein by reference in its entirety.

This application is related to U.S. patent application Ser. Nos.11/693,500 and 11/693,496, each entitled “Percutaneous Spinal Implantsand Methods,” filed on the same date, each of which is incorporatedherein by reference in their entirety.

BACKGROUND

The invention relates generally to the treatment of spinal conditions,and more particularly, to the treatment of spinal compression usingpercutaneous spinal implants for implantation between adjacent spinousprocesses.

A back condition that impacts many individuals is spinal stenosis.Spinal stenosis is a progressive narrowing of the spinal canal thatcauses compression of the spinal cord. Each vertebra in the spinalcolumn has an opening that extends through it. The openings are alignedvertically to form the spinal canal. The spinal cord runs through thespinal canal. As the spinal canal narrows, the spinal cord and nerveroots extending from the spinal cord and between adjacent vertebrae arecompressed and may become inflamed. Spinal stenosis can cause pain,weakness, numbness, burning sensations, tingling, and in particularlysevere cases, may cause loss of bladder or bowel function, or paralysis.The legs, calves and buttocks are most commonly affected by spinalstenosis, however, the shoulders and arms may also be affected.

Mild cases of spinal stenosis may be treated with rest or restrictedactivity, non-steroidal anti-inflammatory drugs (e.g., aspirin),corticosteroid injections (epidural steroids), and/or physical therapy.Some patients find that bending forward, sitting or lying down may helprelieve the pain. This may be due to bending forward creates morevertebral space, which may temporarily relieve nerve compression.Because spinal stenosis is a progressive disease, the source of pressuremay have to be surgically corrected (decompressive laminectomy) as thepatient has increasing pain. The surgical procedure can remove bone andother tissues that have impinged upon the spinal canal or put pressureon the spinal cord. Two adjacent vertebrae may also be fused during thesurgical procedure to prevent an area of instability, improper alignmentor slippage, such as that caused by spondylolisthesis. Surgicaldecompression can relieve pressure on the spinal cord or spinal nerve bywidening the spinal canal to create more space. This procedure requiresthat the patient be given a general anesthesia as an incision is made inthe patient to access the spine to remove the areas that arecontributing to the pressure. This procedure, however, may result inblood loss and an increased chance of significant complications, andusually results in an extended hospital stay.

Minimally-invasive procedures have been developed to provide access tothe space between adjacent spinous processes such that major surgery isnot required. Such known procedures, however, may not be suitable inconditions where the spinous processes are severely compressed.Moreover, such procedures typically involve large or multiple incisions.

Thus, a need exists for improvements in the treatment of spinalconditions such as spinal stenosis.

SUMMARY OF THE INVENTION

Medical devices and related methods for the treatment of spinalconditions are described herein. In some embodiments, an apparatusincludes an elongate member including a cutting edge disposed at adistal end portion of the elongate member. The cutting edge isconfigured to cut a portion of an implant when the elongate member movesrelative to the implant.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a posterior view of a medicaldevice according to an embodiment of the invention in a firstconfiguration adjacent two adjacent spinous processes.

FIG. 2 is a schematic illustration of a posterior view of a medicaldevice according to an embodiment of the invention in a secondconfiguration adjacent two adjacent spinous processes.

FIG. 3 is a schematic illustration of a deforming element according toan embodiment of the invention in a first configuration.

FIG. 4 is a schematic illustration of a side view of the expandingelement illustrated in FIG. 3.

FIG. 5 is a side view of a medical device according to an embodiment ofthe invention in a first configuration.

FIG. 6 is a side view of the medical device illustrated in FIG. 5 in asecond configuration.

FIG. 7 is a perspective view of a medical device according to anembodiment of the invention in a first configuration.

FIG. 8 is a posterior view of a medical device according to anembodiment of the invention, a portion of which is in a secondconfiguration.

FIG. 9 is a posterior view of the medical device illustrated in FIG. 7fully deployed in the second configuration.

FIG. 10 is a front plan view of the medical device illustrated in FIG. 7in the second configuration.

FIG. 11 is a perspective view of an implant expansion device accordingto an embodiment of the invention.

FIG. 12 is an alternative perspective view of the implant expansiondevice illustrated in FIG. 11.

FIG. 13 is a perspective view of a portion of the implant expansiondevice illustrated in FIG. 11.

FIG. 14 is a cross-sectional view of a portion of the device illustratedin FIG. 11, taken along line A-A in FIG. 11.

FIG. 15 is a cross-sectional view of a portion of the device illustratedin FIG. 11 in a first configuration, taken along line B-B in FIG. 11.

FIG. 16 is a cross-sectional view of a portion of the device illustratedin FIG. 11 in a second configuration, taken along line C-C in FIG. 11.

FIG. 17 is a side perspective view of an implant according to anembodiment of the invention shown in a collapsed configuration.

FIG. 18 is a cross-sectional view of the implant of FIG. 17 taken alongline 18-18.

FIG. 19 is a side perspective view of the implant of FIG. 17 shown in anexpanded configuration.

FIG. 20 is a rear perspective view of the implant of FIG. 17 shown in acollapsed configuration.

FIG. 21 is cross-sectional view of the implant of FIG. 17 shown in acollapsed configuration taken along line 21-21.

FIG. 22 is a rear perspective view of an implant according to anembodiment of the invention shown in a collapsed configuration.

FIG. 23 is a cross-sectional view of the implant of FIG. 22 shown in acollapsed configuration.

FIG. 24 is a perspective view of the implant of FIG. 22 in a collapsedconfiguration disposed on an expansion tool according to an embodimentof the invention.

FIG. 25 is a perspective view of the implant and the expansion tool ofFIG. 24 taken along region 25.

FIG. 26 is a side cross-sectional view of the implant and the expansiontool of FIG. 24.

FIG. 27 is a side cross-sectional view of the implant and the expansiontool as shown in FIG. 26 taken along region 27.

FIG. 28 is a perspective view of the implant of FIG. 22 in an expandedconfiguration disposed on an expansion tool according to an embodimentof the invention.

FIG. 29 is a perspective view of the implant and the expansion tool ofFIG. 28 taken along region 29.

FIG. 30 is a side cross-sectional view of the implant and the expansiontool of FIG. 28.

FIG. 31 is a side cross-sectional view of the implant and the expansiontool as shown in FIG. 30 taken along region 31.

FIG. 32 is a schematic illustration of a medical device according to anembodiment of the invention in a collapsed configuration adjacent twospinous processes.

FIG. 33 is a schematic illustration of the medical device of FIG. 32 inan expanded configuration adjacent two spinous processes.

FIG. 34 is a side view of a portion of a medical device including anengaging portion in an extended configuration, according to anembodiment of the invention, positioned adjacent a spinous process.

FIG. 35 is a side view of the portion of the medical device of FIG. 34including the engaging portion in a partially collapsed configuration.

FIG. 36 is a side view of the portion of the medical device of FIG. 34including the engaging portion in the extended configuration after beinginserted past the spinous process.

FIG. 37 is a side perspective view of an implant according to anembodiment of the invention in an expanded configuration.

FIG. 38 is a side perspective view of the implant of FIG. 37 shown in acollapsed configuration.

FIG. 39 is a side perspective view of the medical device of FIG. 37shown in a collapsed configuration.

FIG. 40 is a side view of a deployment tool according to an embodimentof the invention.

FIG. 41 is a side view of a portion of the deployment tool of FIG. 40shown in a first configuration.

FIG. 42 is a side view of the portion of the deployment tool of FIG. 41shown in a second configuration.

FIG. 43 is a side view of a portion of the deployment tool of FIG. 41and the implant of FIG. 37 with the implant shown in an expandedconfiguration.

FIG. 44 is a cross-sectional view of the portion of the deployment tooland implant shown in FIG. 43.

FIG. 45 is a cross-sectional view of the deployment tool and implant ofFIG. 43 with the implant shown in a collapsed configuration positionedbetween adjacent spinous processes.

FIG. 46 is a side perspective view of the implant of FIG. 37 shownrotated about a longitudinal axis of the implant.

FIG. 47 is a side perspective view of an implant according to anotherembodiment of the invention.

FIG. 48 is a side view of a deployment tool according to anotherembodiment of the invention.

FIG. 49 is a side view of a deployment tool according to anotherembodiment of the invention.

FIG. 50 is a side view of a deployment tool according to anotherembodiment of the invention.

FIG. 51 is a side view of a deployment tool according to anotherembodiment of the invention.

FIGS. 52 and 53 are schematic illustrations of a deployment toolaccording to an embodiment of the invention, in a first configurationand a second configuration, respectively.

FIG. 54 is a perspective view of a deployment tool according to anembodiment of the invention.

FIG. 55 is a perspective view of a spinal implant according to anembodiment of the invention.

FIG. 56 is a perspective cross-sectional view of a portion of thedeployment tool shown in FIG. 54.

FIG. 57 is a perspective view of a portion of the deployment tool shownin FIG. 54.

FIG. 58 is a perspective view of a portion of the deployment tool shownin FIG. 54.

FIG. 59 is a perspective view of a portion of the deployment tool shownin FIG. 54.

FIG. 60 is a perspective view of a portion of the deployment tool shownin FIG. 54.

FIG. 61 is a front cross-sectional view of a portion of the deploymenttool shown in FIG. 54 in a first configuration.

FIG. 62 is a front cross-sectional view of a portion of the deploymenttool shown in FIG. 54 in a second configuration.

FIGS. 63 and 64 are schematic illustrations of a deployment toolaccording to an embodiment of the invention, in a first configurationand a second configuration, respectively.

FIGS. 65 and 66 are schematic illustrations of a deployment toolaccording to an embodiment of the invention, in a first configurationand a second configuration, respectively.

FIG. 67 is a perspective view of a deployment tool according to anembodiment of the invention.

FIG. 68 is a front cross-sectional view of a spinal implant according toan embodiment of the invention.

FIG. 69 is a perspective view of a portion of the deployment tool shownas region 69 in FIG. 67.

FIG. 70 is a front cross-sectional view of the portion of the deploymenttool shown in FIG. 69 taken along line 70-70 in FIG. 69.

FIGS. 71-73 are a front cross-sectional views of the portion of thedeployment tool shown in FIG. 69 and the spinal implant shown in FIG. 68in a first configuration, a second configuration and a thirdconfiguration, respectively.

FIG. 74 is a schematic illustration of a deployment tool according to anembodiment of the invention.

FIG. 75 is a front view of a deployment tool according to an embodimentof the invention.

FIG. 76 is a side view of the deployment tool shown in FIG. 75.

FIGS. 77 and 80 are a front view of the deployment tool shown in FIG. 75in a first configuration and a second configuration, respectively.

FIGS. 78 and 79 are side views of the deployment tool shown in FIG. 75in a first configuration and a second configuration, respectively.

FIG. 81 is a front view of the deployment tool shown in FIG. 75 in athird configuration.

FIGS. 82 and 83 are schematic illustrations of a medical deviceaccording to an embodiment of the invention, in a first configurationand a second configuration, respectively.

FIG. 84 is a top view schematic illustration of the medical device shownin FIG. 83, in the second configuration.

FIGS. 85-87 are cross-sectional front views of a medical deviceaccording to an embodiment of the invention, in a first configuration, asecond configuration and a third configuration, respectively.

FIG. 88 is a schematic illustration of a medical device according to anembodiment of the invention.

FIG. 89 is a flow chart of a method according to an embodiment of theinvention.

FIG. 90 is a flow chart of a method according to an embodiment of theinvention.

FIG. 91 is a flow chart of a method according to an embodiment of theinvention.

FIG. 92 is a flow chart of a method according to an embodiment of theinvention.

DETAILED DESCRIPTION

As used in this specification and the appended claims, the singularforms “a,” “an” and “the” include plural referents unless the contextclearly dictates otherwise. Thus, for example, the term “a member” isintended to mean a single member or a combination of members, “amaterial” is intended to mean one or more materials, or a combinationthereof. Furthermore, the words “proximal” and “distal” refer todirection closer to and away from, respectively, an operator (e.g.,surgeon, physician, nurse, technician, etc.) who would insert themedical device into the patient, with the tip-end (i.e., distal end) ofthe device inserted inside a patient's body first. Thus, for example,the implant end first inserted inside the patient's body would be thedistal end of the implant, while the implant end to last enter thepatient's body would be the proximal end of the implant.

In some embodiments, an apparatus includes an elongate member configuredto engage a spinal implant and a locking member. The locking member isdisposed at a distal end portion of the elongate member. The lockingmember is configured to move relative to the elongate member between afirst position and a second position in a direction substantiallyperpendicular to a center line of the elongate member. The lockingmember is configured to allow the distal end portion of the elongatemember to move relative to the spinal implant when in the firstposition. The locking member is configured to couple the distal endportion of the elongate member to the spinal implant when in the secondposition.

In some embodiments, an apparatus includes an elongate member configuredto engage a spinal implant, a sleeve and a locking member. The lockingmember is disposed at a distal end portion of the elongate member. Thelocking member is configured to move relative to the elongate memberbetween a first position and a second position in a directionsubstantially perpendicular to a center line of the elongate member. Thelocking member is configured to allow the distal end portion of theelongate member to move relative to the spinal implant when in the firstposition. The locking member is configured complimentarily fit with anopening defined by the spinal implant to couple the distal end portionof the elongate member to the spinal implant when in the secondposition. The sleeve is disposed about an outer surface of the elongatemember and is configured to retain the locking member within the openingwhen the sleeve is in a first position.

In some embodiments, an apparatus includes a first elongate memberconfigured to engage a spinal implant, a second elongate member movablydisposed within the first elongate member, and a locking member. Thelocking member is disposed at a distal end portion of the elongatemember. The locking member is configured to move relative to the firstelongate member between a first position and a second position in adirection substantially perpendicular to a center line of the firstelongate member. The locking member is configured to allow the distalend portion of the first elongate member to move relative to the spinalimplant when in the first position. The locking member is configured tocouple the distal end portion of the first elongate member to the spinalimplant when in the second position. The second elongate member isconfigured to move an inner member of the spinal implant relative to aportion of an outer member of the spinal implant when the locking memberis in the second position.

In some embodiments, an apparatus includes an elongate member and alocking member. The elongate member has a distal end portion configuredto be removably disposed within an interior portion of a spinal implant.The locking member is configured to releasably couple the distal endportion of the elongate member to the spinal implant. The lockingmember, which can be, for example, a ball, a pin and/or a retainingring, is configured to be disposed substantially within the interiorportion of the spinal implant such that the elongate member movesrelative to the spinal implant when the locking member is in a firstconfiguration. The locking member is configured to engage a surfacedefining the interior portion of the spinal implant such that theelongate member cannot substantially move relative to the spinal implantwhen the locking member is in a second configuration.

In some embodiments, an apparatus includes an elongate member configuredto engage a spinal implant, a locking member and an actuator. Thelocking member is disposed at a distal end portion of the elongatemember and has a first configuration and a second configuration. Thelocking member is configured to allow the distal end portion of theelongate member to move relative to the spinal implant when in the firstconfiguration. The locking member is configured to couple the distal endportion of the elongate member to the spinal implant when in the secondconfiguration. The actuator is disposed at the distal end portion of theelongate member and is configured to move the locking member from itsfirst configuration to its second configuration when the elongate memberengages the spinal implant. The actuator can be any suitable actuator,such as for example, a mechanical actuator (e.g., a spring-loadedactuator), a pneumatic actuator, a hydraulic actuator and/or anelectronic actuator.

In some embodiments, an apparatus includes a first elongate member, asecond elongate member and a connector. The second elongate member ismovably disposed within a distal end portion of the first elongatemember. The second elongate member is configured to engage an innermember of a spinal implant disposed within an outer member of the spinalimplant. The connector, which is disposed at the distal end portion ofthe first elongate member, is configured to releasably connect thedistal end portion of the first elongate member to the outer member ofthe spinal implant.

In some embodiments, an apparatus includes an elongate member and aconnector disposed at a distal end portion of the elongate member. Theconnector is configured to rotate relative to the elongate memberbetween a first position and a second position about a center line ofthe elongate member between a first position and a second position. Theconnector is configured to allow the distal end portion of the elongatemember to move relative to a spinal implant when the connector is in thefirst position. The connector is configured to connect the distal endportion of the elongate member to the spinal implant when the connectoris in the second position. In some embodiments, for example, theconnector can include multiple tines configured to complimentarily fitwith an opening defined by the spinal implant when the connector is inthe second position.

In some embodiments, an apparatus includes and elongate member includinga cutting edge disposed at a distal end portion of the elongate member.The cutting edge is configured to cut a portion of a spinal implant whenthe elongate member moves relative to the spinal implant.

In some embodiments, an apparatus includes and elongate member and acutting member. The cutting member is coupled to a distal end portion ofthe first elongate member. The cutting member configured to cut aportion of a spinal implant. In some embodiments, for example, thecutting member can move relative to the elongate member such that thecutting member cuts the portion of the spinal implant.

In some embodiments, a method includes inserting an elongate member intoa body. The elongate member defines a center line and has a distal endportion. A locking member is disposed at the distal end portion of theelongate member. The distal end portion of the elongate member is movedinto engagement with a spinal implant disposed within the body beforethe elongate member is inserted into the body. The locking member ismoved relative to the elongate member between a first position and asecond position in a direction substantially perpendicular to the centerline such that the distal end portion of the elongate member is coupledto the spinal implant.

In some embodiments, a method includes inserting an elongate member intoa body. A distal end portion of the elongate member is coupled to anouter member of a spinal implant disposed within the body before theelongate member is inserted into the body. An inner member of the spinalimplant is moved relative to the outer member of the spinal implantafter the distal end portion of the elongate member is coupled to theouter member of the spinal implant.

In some embodiments, a method includes coupling a distal end portion ofan elongate member to a spinal implant disposed within a body. A portionof the spinal implant is cut with a cutting edge disposed at the distalend portion of the elongate member. In some embodiments, for example, aretention member of the spinal implant is cut with the cutting edge. Insome embodiments, the method further includes deforming the portion ofthe spinal implant, either plastically or elastically, after it has beencut.

FIG. 1 is a schematic illustration of a medical device according to anembodiment of the invention adjacent two adjacent spinous processes. Themedical device 10 includes a proximal portion 12, a distal portion 14and a central portion 16. The medical device 10 has a firstconfiguration in which it can be inserted between adjacent spinousprocesses S. The central portion 16 is configured to contact the spinousprocesses S to prevent over-extension/compression of the spinousprocesses S. In some embodiments, the central portion 16 does notsubstantially distract the adjacent spinous processes S. In otherembodiments, the central portion 16 does not distract the adjacentspinous processes S.

In the first configuration, the proximal portion 12, the distal portion14 and the central portion 16 are coaxial (i.e., share a commonlongitudinal axis). In some embodiments, the proximal portion 12, thedistal portion 14 and the central portion 16 define a tube having aconstant inner diameter. In other embodiments, the proximal portion 12,the distal portion 14 and the central portion 16 define a tube having aconstant outer diameter and/or inner diameter.

The medical device 10 can be moved from the first configuration to asecond configuration as illustrated in FIG. 2. In the secondconfiguration, the proximal portion 12 and the distal portion 14 arepositioned to limit lateral movement of the device 10 with respect tothe spinous processes S. The proximal portion 12 and the distal portion14 are configured to engage the spinous process (i.e., either directlyor through surrounding tissue) in the second configuration. For purposesof clarity, the tissue surrounding the spinous processes S is notillustrated.

In some embodiments, the proximal portion 12, the distal portion 14 andthe central portion 16 are monolithically formed. In other embodiments,one or more of the proximal portion 12, the distal portion 14 and thecentral portion 16 are separate components that can be coupled togetherto form the medical device 10. For example, the proximal portion 12 anddistal portion 14 can be monolithically formed and the central portioncan be a separate component that is coupled thereto.

In use, the spinous processes S can be distracted prior to inserting themedical device 10. Distraction of spinous processes is discussed below.When the spinous processes are distracted, a trocar can be used todefine an access passage for the medical device 10. In some embodiments,the trocar can be used to define the passage as well as distract thespinous processes S. Once an access passage is defined, the medicaldevice 10 is inserted percutaneously and advanced between the spinousprocesses, distal end 14 first, until the central portion 16 is locatedbetween the spinous processes S. Once the medical device 10 is in placebetween the spinous processes, the proximal portion 12 and the distalportion 14 are moved to the second configuration, either serially orsimultaneously.

In some embodiments, the medical device 10 is inserted percutaneously(i.e., through an opening in the skin) and in a minimally-invasivemanner. For example, as discussed in detail herein, the size of portionsof the implant is expanded after the implant is inserted between thespinous processes. Once expanded, the size of the expanded portions ofthe implant is greater than the size of the opening. For example, thesize of the opening/incision in the skin may be between 3 millimeters inlength and 25 millimeters in length. In some embodiments, the size ofthe implant in the expanded configuration is between 3 and 25millimeters.

FIG. 3 is a schematic illustration of a deformable element 18 that isrepresentative of the characteristics of, for example, the distalportion 14 of the medical device 10 in a first configuration. Thedeformable member 18 includes cutouts A, B, C along its length to defineweak points that allow the deformable member 18 to deform in apredetermined manner. Depending upon the depth d of the cutouts A, B, Cand the width w of the throats T1, T2, T3, the manner in which thedeformable member 18 deforms under an applied load can be controlled andvaried. Additionally, depending upon the length L between the cutouts A,B, C (i.e., the length of the material between the cutouts) the mannerin which the deformable member 18 deforms can be controlled and varied.

FIG. 4 is a schematic illustration of the expansion properties of thedeformable member 18 illustrated in FIG. 3. When a load is applied, forexample, in the direction indicated by arrow X, the deformable member 18deforms in a predetermined manner based on the characteristics of thedeformable member 18 as described above. As illustrated in FIG. 4, thedeformable member 18 deforms most at cutouts B and C due to theconfiguration of the cutout C and the short distance between cutouts Band C. In some embodiments, the length of the deformable member 18between cutouts B and C is sized to fit adjacent a spinous process.

The deformable member 18 is stiffer at cutout A due to the shallow depthof cutout A. As indicated in FIG. 4, a smooth transition is defined bythe deformable member 18 between cutouts A and B. Such a smoothtransition causes less stress on the tissue surrounding a spinousprocess than a more drastic transition such as between cutouts B and C.The dimensions and configuration of the deformable member 18 can alsodetermine the timing of the deformation at the various cutouts. Theweaker (i.e., deeper and wider) cutouts deform before the stronger(i.e., shallower and narrower) cutouts.

FIGS. 5 and 6 illustrate a spinal implant 100 in a first configurationand second configuration, respectively. As shown in FIG. 5, the spinalimplant 100 is collapsed in a first configuration and can be insertedbetween adjacent spinous processes. The spinal implant 100 has a firstexpandable portion 110, a second expandable portion 120 and a centralportion 150. The first expandable portion 110 has a first end 112 and asecond end 1140. The second expandable portion 120 has a first end 122and a second end 124. The central portion 150 is coupled between secondend 1140 and first end 122. In some embodiment, the spinal implant 100is monolithically formed.

The first expandable portion 110, the second expandable portion 120 andthe central portion 150 have a common longitudinal axis A along thelength of spinal implant 100. The central portion 150 can have the sameinner diameter as first expandable portion 110 and the second expandableportion 120. In some embodiments, the outer diameter of the centralportion 150 is smaller than the outer diameter of the first expandableportion 110 and the second expandable portion 120.

In use, spinal implant 100 is inserted percutaneously between adjacentspinous processes. The first expandable portion 110 is inserted firstand is moved past the spinous processes until the central portion 150 ispositioned between the spinous processes. The outer diameter of thecentral portion 150 can be slightly smaller than the space between thespinous processes to account for surrounding ligaments and tissue. Insome embodiments, the central portion directly contacts the spinousprocesses between which it is positioned. In some embodiments, thecentral portion of spinal implant 100 is a fixed size and is notcompressible or expandable.

The first expandable portion 110 includes expanding members 115, 117 and119. Between the expanding members 115, 117, 119, openings 111 aredefined. As discussed above, the size and shape of the openings 111influence the manner in which the expanding members 115, 117, 119 deformwhen an axial load is applied. The second expandable portion 120includes expanding members 125, 127 and 129. Between the expandingmembers 125, 127, 129, openings 121 are defined. As discussed above, thesize and shape of the openings 121 influence the manner in which theexpanding members 125, 127, 129 deform when an axial load is applied.

When an axial load is applied to the spinal implant 100, the spinalimplant 100 expands to a second configuration as illustrated in FIG. 6.In the second configuration, first end 112 and second end 1140 of thefirst expandable portion 110 move towards each other and expandingmembers 115, 117, 119 project substantially laterally away from thelongitudinal axis A. Likewise, first end 122 and second end 124 of thesecond expandable portion 120 move towards one another and expandingmembers 125, 127, 129 project laterally away from the longitudinal axisA. The expanding members 115, 117, 119, 125, 127, 129 in the secondconfiguration form projections that extend to positions adjacent to thespinous processes between which the spinal implant 100 is inserted. Inthe second configuration, the expanding members 115, 117, 119, 125, 127,129 inhibit lateral movement of the spinal implant 100, while thecentral portion 150 prevents the adjacent spinous processes from movingtogether any closer than the distance defined by the diameter of thecentral portion 150.

A spinal implant 200 according to an embodiment of the invention isillustrated in FIGS. 7-9 in various configurations. Spinal implant 200is illustrated in a completely collapsed configuration in FIG. 7 and canbe inserted between adjacent spinous processes. The spinal implant 200has a first expandable portion 210, a second expandable portion 220 anda central portion 250. The first expandable portion 210 has a first end212 and a second end 214. The second expandable portion 220 has a firstend 222 and a second end 224. The central portion 250 is coupled betweensecond end 214 and first end 222.

The first expandable portion 210, the second expandable portion 220 andthe central portion 250 have a common longitudinal axis A along thelength of spinal implant 200. The central portion 250 can have the sameinner diameter as first expandable portion 210 and the second expandableportion 220. The outer diameter of the central portion 250 is greaterthan the outer diameter of the first expandable portion 210 and thesecond expandable portion 220. The central portion 250 can bemonolithically formed with the first expandable portion 210 and thesecond expandable portion 220 or can be a separately formed sleevecoupled thereto or thereupon.

In use, spinal implant 200 is inserted percutaneously between adjacentspinous processes S. The first expandable portion 210 is inserted firstand is moved past the spinous processes S until the central portion 250is positioned between the spinous processes S. The outer diameter of thecentral portion 250 can be slightly smaller than the space between thespinous processes S to account for surrounding ligaments and tissue. Insome embodiments, the central portion 250 directly contacts the spinousprocesses S between which it is positioned. In some embodiments, thecentral portion 250 of spinal implant 200 is a fixed size and is notcompressible or expandable. In other embodiments, the central portion250 can compress to conform to the shape of the spinous processes.

The first expandable portion 210 includes expanding members 215, 217 and219. Between the expanding members 215, 217, 219, openings 211 aredefined. As discussed above, the size and shape of the openings 211influence the manner in which the expanding members 215, 217, 219 deformwhen an axial load is applied. Each expanding member 215, 217, 219 ofthe first expandable portion 210 includes a tab 213 extending into theopening 211 and an opposing mating slot 218. In some embodiments, thefirst end 212 of the first expandable portion 210 is rounded tofacilitate insertion of the spinal implant 200.

The second expandable portion 220 includes expanding members 225, 227and 229. Between the expanding members 225, 227, 229, openings 221 aredefined. As discussed above, the size and shape of the openings 221influence the manner in which the expanding members 225, 227, 229 deformwhen an axial load is applied. Each expanding member 225, 227, 229 ofthe second expandable portion 220 includes a tab 223 extending into theopening 221 and an opposing mating slot 228.

When an axial load is applied to the spinal implant 200, the spinalimplant moves to a partially expanded configuration as illustrated inFIG. 8. In the partially expanded configuration, first end 222 andsecond end 224 of the second expandable portion 220 move towards oneanother and expanding members 225, 227, 229 project laterally away fromthe longitudinal axis A. To prevent the second expandable portion 220from over-expanding, the tab 223 engages slot 228 and acts as a positivestop. As the axial load continues to be imparted to the spinal implant200 after the tab 223 engages slot 228, the load is transferred to thefirst expandable portion 210. Accordingly, the first end 212 and thesecond end 214 then move towards one another until tab 213 engages slot218 in the fully expanded configuration illustrated in FIG. 9. In thesecond configuration, expanding members 215, 217, 219 project laterallyaway from the longitudinal axis A. In some alternative embodiments, thefirst expandable portion and the second expandable portion expandsimultaneously under an axial load.

The order of expansion of the spinal implant 200 can be controlled byvarying the size of openings 211 and 221. For example, in theembodiments shown in FIGS. 7-9, the opening 221 is slightly larger thanthe opening 211. Accordingly, the notches 226 are slightly larger thanthe notches 216. As discussed above with respect to FIGS. 3 and 4, forthis reason, the second expandable portion 220 will expand before thefirst expandable portion 210 under an axial load.

In the second configuration, the expanding members 215, 217, 219, 225,227, 229 form projections that extend adjacent the spinous processes S.Once in the second configuration, the expanding members 215, 217, 219,225, 227, 229 inhibit lateral movement of the spinal implant 200, whilethe central portion 250 prevents the adjacent spinous processes frommoving together any closer than the distance defined by the diameter ofthe central portion 250.

The portion P of each of the expanding members 215, 217, 219, 225, 227,229 proximal to the spinous process S expands such that portion P issubstantially parallel to the spinous process S. The portion D of eachof the expanding members 215, 217, 219, 225, 227, 229 distal from thespinous process S is angled such that less tension is imparted to thesurrounding tissue.

In the second configuration, the expanding members 225, 227, 229 areseparate by approximately 120 degrees from an axial view as illustratedin FIG. 10. While three expanding members are illustrated, two or moreexpanding members may be used and arranged in an overlapping orinterleaved fashion when multiple implants 200 are inserted betweenmultiple adjacent spinous processes. Additionally, regardless of thenumber of expanding members provided, the adjacent expanding membersneed not be separated by equal angles or distances.

The spinal implant 200 is deformed by a compressive force impartedsubstantially along the longitudinal axis A of the spinal implant 200.The compressive force is imparted, for example, by attaching a rod (notillustrated) to the first end 212 of the first expandable portion 210and drawing the rod along the longitudinal axis while imparting anopposing force against the second end 224 of the second expandableportion 220. The opposing forces result in a compressive force causingthe spinal implant 200 to expand as discussed above.

The rod used to impart compressive force to the spinal implant 200 canbe removably coupled to the spinal implant 200. For example, the spinalimplant 200 can include threads 208 at the first end 212 of the firstexpandable portion 210. The force opposing that imparted by the rod canbe applied by using a push bar (not illustrated) that is removablycoupled to the second end 224 of the second expandable portion 220. Thepush rod can be aligned with the spinal implant 200 by an alignmentnotch 206 at the second end 224. The spinal implant 200 can also bedeformed in a variety of other ways, using a variety of expansiondevices (also referred to herein as insertion tools, deployment toolsand/or removal tools). While various types of implants are illustratedwith various types of expansion devices, the expansion devices describedherein can be used with any of the implants described herein.

FIGS. 11-16 illustrate an expansion device 1500 (also referred to hereinas an insertion tool or a deployment tool) according to an embodiment ofthe invention. Although no particular implant is illustrated in FIGS.11-16, any of the implants described herein, such as, for example,implant 200 (see FIG. 7), can be used with the expansion device 1500.The expansion device 1500 includes a guide handle 1510, a knob assembly1515, a shaft 1520, a rod 1570 and an implant support portion 1530. Theexpansion device 1500 is used to insert an implant (not illustrated) inbetween adjacent spinous processes and expand the implant such that itis maintained in position between the spinous processes as describedabove. Both the guide handle 1510 and the knob assembly 1515 can begrasped to manipulate the expansion device 1500 to insert the implant.As described in more detail herein, the knob assembly 1515 is configuredsuch that as the knob assembly 1515 is actuated, the rod 1570 translatesand/or rotates within the shaft 1520; when the rod 1570 translates, theimplant (not illustrated) is moved between its collapsed configurationand its expanded configuration; when the rod 1570 rotates, the implantis disengaged from the rod 1570.

As best illustrated in FIGS. 15 and 16, the implant support portion 1530includes a receiving member 1538 and a spacer 1532. The receiving member1538 includes a side wall 1540 that is coupled to and supported by thedistal end of the shaft 1520. The side wall 1540 defines an alignmentprotrusion 1536 and a receiving area 1542 configured to receive aportion of the spacer 1532. The implant slides over spacer 1532 untilits proximal end is received within a recess 1534 defined by the sidewall 1540 and the outer surface of the spacer 1532. The alignmentprotrusion 1536 is configured to mate with a corresponding notch on theimplant (see, e.g., alignment notch 206 in FIG. 7) to align the implantwith respect to the expansion device. Once the implant is aligned withinthe implant support portion 1530, the distal end of the implant isthreadedly coupled to the distal end of rod 1570.

As illustrated, the spacer 1532 ensures that the implant is alignedlongitudinally during the insertion and expansion process. The spacer1532 can also be configured to maintain the shape of the implant duringinsertion and to prevent the expandable portions of the implant fromextending inwardly during deployment of the implant. For example, insome embodiments, the spacer 1532 can be constructed from a solid,substantially rigid material, such as stainless steel, having an outerdiameter and length corresponding to the inner diameter and length ofthe implant. In other embodiments, the expansion device can beconfigured to be used with implants that include an inner coreconfigured to provide structural support to the implant (see, forexample, FIGS. 17-23). In such embodiments, as described in more detailherein, the spacer of the insertion tool can be configured to cooperatewith the inner core of the implant to provide the alignment andstructural support of the implant during insertion and expansion.

The knob assembly 1515 includes an upper housing 1517 that threadedlyreceives the shaft 1520, an actuator knob 1550 and a release knob 1560as best illustrated in FIG. 14. Upper housing 1517 includes internalthreads 1519 that mate with external threads 1521 on shaft 1520. Theproximal end of rod 1570 is coupled to the knob assembly 1515 by anadapter 1554, which is supported by two thrust bearings 1552. Actuatorknob 1550 is coupled to the upper housing 1517 and is engaged with theadapter 1554 such that when actuator knob 1550 is turned in thedirection indicated by arrows E (see FIG. 13), the rod 1570 translatesaxially relative to the shaft 1520 towards the proximal end of thedevice 1500, thereby acting as a draw bar and opposing the movement ofthe implant in the distal direction. In other words, when the implant isinserted between adjacent spinous processes and the actuator knob 1515is turned, the distal end of the implant support portion 1530 imparts anaxial force against the proximal end of the implant, while the rod 1570causes an opposing force in the proximal direction. In this manner, theforces imparted by the implant support portion and the rod 1570 causeportions of the implant to expand in a transverse configuration suchthat the implant is maintained in position between the spinous processesas described above. The expansion device 1500 can also be used to movethe implant from its expanded configuration to its collapsedconfiguration by turning the actuator knob 1550 in the oppositedirection.

Once the implant is in position and fully expanded, the release knob1560 is turned in the direction indicated by arrow R (see FIG. 13)thereby causing the rod 1570 to rotate within the shaft 1520. In thismanner, the implant can be disengaged from the rod 1570. During thisoperation, the implant is prevented from rotating by the alignmentprotrusion 1536, which is configured to mate with a corresponding notchon the implant. Once the implant is decoupled from the rod 1570, theexpansion tool 1500 can then be removed from the patient.

Although the knob assembly 1515 is shown and described as including anactuator knob 1550 and a release knob 1560 that are coaxially arrangedwith a portion of the release knob 1560 being disposed within theactuator knob 1550, in some embodiments, the release knob is disposedapart from the actuator knob. In other embodiments, the release knob andthe actuator knob are not coaxially located. In yet other embodiments,the knob assembly 1515 does not include knobs having a circular shape,but rather includes levers, handles or any other device suitable foractuating the rod relative to the shaft as described above.

FIGS. 17-23 illustrate an implant 6610 according to another embodimentof the invention. The implant 6610 can be moved between a collapsedconfiguration, as shown in FIGS. 17 and 18, and an expandedconfiguration, as shown in FIGS. 19-23. The implant 6610 includes anouter shell 6670 having a distal portion 6612, a proximal portion 6614,and a central portion 6616. The outer shell 6670 defines a series ofopenings 6618 disposed between the distal portion 6612 and the centralportion 6616, and the proximal portion 6614 and the central portion6616. The outer shell 6670 includes a series of tabs 6620, a pair ofwhich are disposed opposite each other, along the longitudinal axis ofthe implant 6610, on either side of each opening 6618. The outer shell6670 also includes expandable portions 6640, which form extensions 6642that extend radially from the outer shell 6670 when the implant 6610 isin the expanded configuration. As illustrated best in FIGS. 19-23, thearrangement of the openings 6618 and the tabs 6620 effect the shapeand/or size of the extensions 6642. In some embodiments, the opposingtabs 6620 can be configured to engage each other when the implant 6610is in the expanded configuration, thereby serving as a positive stop tolimit the amount of expansion. In other embodiments, for example, theopposing tabs 6620 can be configured to engage each other during theexpansion process, thereby serving as a positive stop, but remain spacedapart when the implant 6610 is in the expanded configuration (see, forexample, FIGS. 19-23). In such embodiments, the elastic properties ofthe extensions 6642 can cause a slight “spring back,” thereby causingthe opposing tabs 6620 to be slightly spaced apart when the expansiondevice (also referred to as an insertion tool or a deployment tool) isdisengaged from the implant 6610.

As illustrated best in FIG. 17, when the implant is in the collapsedconfiguration, the expandable portions 6640 are contoured to extendslightly radially from remaining portions of the outer shell 6670. Inthis manner, the expandable portions 6640 are biased such that when acompressive force is applied, the expandable portions 6640 will extendoutwardly from the outer shell 6670. The expandable portions 6640 can bebiased using any suitable mechanism. In some embodiments, for example,the expandable portions can be biased by including a notch in one ormore locations along the expandable portion, as previously described. Inother embodiments, the expandable portions can be biased by varying thethickness of the expandable portions in an axial direction. In yet otherembodiments, the expandable portions can be stressed or bent prior toinsertion such that the expandable portions are predisposed to extendoutwardly when a compressive force is applied to the implant. In suchembodiments, the radius of the expandable portions is greater than thatof the remaining portions of the implant (e.g., the remainingcylindrical portions of the implant).

The implant 6610 also includes an inner core 6672 disposed within alumen 6658 defined by the outer shell 6670. The inner core 6672 isconfigured to maintain the shape of the implant 6610 during insertion,to prevent the expandable portions from extending inwardly into a regioninside of the outer shell 6670 during deployment and/or to maintain theshape of the central portion 6616 once the implant is in its desiredposition. As such, the inner core 6670 can be constructed to provideincreased compressive strength to the outer shell 6670. In other words,the inner core 6672 can provide additional structural support to outershell 6670 (e.g., in a direction transverse to the axial direction) byfilling at least a portion of the region inside outer shell 6670 (e.g.,lumen 6658) and contacting the walls of outer shell 6670. This canincrease the amount of compressive force that can be applied to theimplant 6610 while the implant 6610 still maintains its shape and, forexample, the desired spacing between adjacent spinous processes. In someembodiments, the inner core 6672 can define a lumen 6673, while in otherembodiments, the inner core 6672 can have a substantially solidconstruction. As illustrated, the inner core 6672 is fixedly coupled tothe outer shell 6670 with a coupling portion 6674, which is configuredto be threadedly coupled to the distal portion 6612 of the outer shell6670. The distal end of the coupling portion 6674 of the inner core 6672includes an opening 6675 configured to receive a tool configured todeform the distal end of the coupling portion 6674. In this manner oncethe inner core 6672 is threadedly coupled to the outer shell 6670, thecoupling portion 6674 can be deformed or peened to ensure that the innercore 6672 does not become inadvertently decoupled from the outer shell6670. In some embodiments, an adhesive, such as a thread-lockingcompound can be applied to the threaded portion of the coupling portion6674 to ensure the that the inner core 6672 does not inadvertentlybecome decoupled from the outer shell 6670. Although illustrated asbeing threadedly coupled, the inner core 6672 can be coupled to theouter shell 6670 by any suitable means. In some embodiments, forexample, the inner core 6672 can be coupled to the central portion 6616of the outer shell 6670 by, for example, a friction fit. In otherembodiments, the inner core 6672 can be coupled to the outer shell 6670by an adhesive. The inner core 6672 can have a length such that theinner core 6672 is disposed within the lumen 6658 along substantiallythe entire length of the outer shell 6670 or only a portion of thelength of the outer shell 6670.

The proximal portion of the inner core 6672 includes an opening 6673configured to receive a portion of an expansion device 7500 (alsoreferred to as an insertion tool or a deployment tool), as shown inFIGS. 24-31. The expansion device 7500 is similar to the expansiondevice 1500 shown and described above (see e.g. FIGS. 11-16). Theexpansion device 7500 differs, however, from expansion device 1500 inthat the expansion device 7500 includes spacer 7532 configured tocooperate with the inner core 6672 of the implant 6610. In such anarrangement, the threaded portion of rod 7570 of the expansion device7500 removably engages to the internal threads 6676 of the inner core6672 of the implant 6610, rather than coupling directly to the distalportion of the implant (as shown in FIGS. 15 and 16). Although the innercore 6672 is shown as being threadedly coupled to the expansion device7500, the inner core 6672 can be removably coupled to the expansiondevice 7500 by any suitable means, such as a protrusion and detentarrangement.

In use, once the implant 6610 is positioned on the implant supportportion 7530 of the expansion tool 7500 (see FIGS. 24 and 25), theimplant is inserted into the patient's body and disposed betweenadjacent spinous processes. Once disposed between adjacent spinousprocesses, the expansion device can be used to move the inner core 6672axially towards the proximal portion 6614 of the implant 6610 whilesimultaneously maintaining the position of the proximal portion 6614 ofthe implant 6610, as shown in FIGS. 29 and 31. In this manner, acompressive force is applied along the longitudinal axis of the outershell 6670, thereby causing the outer shell 6670 to fold or bend to formextensions 6642 as described above. As illustrated, a portion of thespacer 7532 is received within the receiving area 7542 of the supportportion 7530 as the implant 6610 is placed in the expandedconfiguration. Similarly, to move the implant 6610 from the expandedconfiguration to the collapsed configuration, the expansion device isactuated in the opposite direction to impart an axial force on thedistal portion 6612 of the outer shell 6610 in a distal direction,moving the distal portion 6612 distally, and moving the implant 6610 tothe collapsed configuration.

Once the implant 6610 is in its expanded configuration (see FIGS.28-31), the implant 6610 can be disengaged from the expansion device7500 by disengaging the distal portion of the rod 7570 from the opening6673. The rod 7570 can be disengaged by actuating the knob assembly 7515rotate the rod 7570 relative to the shaft 7520, as discussed above.

Although shown and described above without reference to any specificdimensions, in some embodiments, the outer shell 6670 can have acylindrical shape having a length of approximately 34.5 mm (1.36 inches)and a diameter between 8.1 and 14.0 mm (0.32 and 0.55 inches). In someembodiments, the wall thickness of the outer shell can be approximately5.1 mm (0.2 inches).

Similarly, in some embodiments, the inner core 6672 can have acylindrical shape having an overall length of approximately 27.2 mm(1.11 inches) and a diameter between 8.1 and 14.0 mm (0.32 and 0.55inches).

In some embodiments, the shape and size of the openings 6618 locatedadjacent the distal portion 6612 can be the same as that for theopenings 6618 located adjacent the proximal portion 6614. In otherembodiments, the openings 6618 can have different sizes and/or shapes.In some embodiments, the openings 6618 can have a length ofapproximately 11.4 mm (0.45 inches) and a width between 4.6 and 10 mm(0.18 and 0.40 inches).

Similarly, the shape and size of the tabs 6620 can be uniform ordifferent as circumstances dictate. In some embodiments, for example,the longitudinal length of the tabs 6620 located adjacent the proximalportion 6614 can be shorter than the longitudinal length of the tabs6620 located adjacent the distal portion 6612. In this manner, as theimplant is moved from the collapsed configuration to the expandedconfiguration, the tabs adjacent the distal portion will engage eachother first, thereby limiting the expansion of the expandable portions6640 adjacent the distal portion 6612 to a greater degree than theexpandable portions 6642 located adjacent the proximal portion 6614. Inother embodiments, the longitudinal length of the tabs can be the same.In some embodiments, the longitudinal length of the tabs can be between1.8 and 2.8 mm (0.07 and 0.11 inches). In some embodiments, the endportions of opposing tabs 6620 can have mating shapes, such as matingradii of curvature, such that the opposing tabs 6620 engage each otherin a predefined manner.

Although illustrated as having a generally rectangular shape, theexpandable portions 6640 and the resulting extensions 6642 can be of anysuitable shape and size. In some embodiments, for example, theexpandable portions can have a longitudinal length of approximately 11.4mm (0.45 inches) and a width between 3.6 and 3.8 mm (0.14 and 0.15inches). In other embodiments, size and/or shape of the expandableportions located adjacent the proximal portion 6614 can be differentthan the size and/or shape of the tabs 6620 located adjacent the distalportion 6612. Moreover, as described above, the expandable portions 6640can be contoured to extend slightly radially from the outer shell 6670.In some embodiments, for example, the expandable portions can have aradius of curvature of approximately 12.7 mm (0.5 inches) along an axisnormal to the longitudinal axis of the implant.

In some embodiments, the expandable portions 6640 and the outer shell6670 are monolithically formed. In other embodiments, the expandableportions 6640 and the outer shell 6670 are formed from separatecomponents having different material properties. For example, theexpandable portions 6640 can be formed from a material having a greateramount of flexibility, while the outer shell 6670 can be formed from amore rigid material. In this manner, the expandable portions 6640 can beeasily moved from the collapsed configuration to the expandedconfiguration, while the outer shell 6670 is sufficiently strong toresist undesirable deformation when in use.

In one embodiment, an apparatus includes a first body coupled to asecond body. The first body and the second body collectively areconfigured to be releasably coupled to an implant device configured tobe disposed between adjacent spinous processes. A first engaging portionis coupled to the first body, and a second engaging portion is coupledto the second body. The first engaging portion and/or the secondengaging portion is configured to be received within a first openingdefined by the implant device. The first body configured to be movedrelative to the second body such that a distance between the firstengaging portion and the second engaging portion is moved between afirst distance and a second distance, and simultaneously a length of theimplant device is moved between a first length and a second length.

In another embodiment, a kit includes an implant that is reconfigurablebetween an expanded configuration and a collapsed configuration whiledisposed between adjacent spinous processes. The implant has alongitudinal axis and defines an opening. A deployment tool isconfigured to be releasably coupled to the implant. The deployment toolincludes an engaging portion configured to be removably received withinthe opening of the implant and extend in a transverse direction relativeto the longitudinal axis when the deployment tool is coupled to theimplant. The deployment tool is configured to move the implant betweenthe collapsed configuration and the expanded configuration while theimplant is disposed between the adjacent spinous processes.

FIGS. 32 and 33 are schematic illustrations of a medical deviceaccording to an embodiment of the invention positioned between twoadjacent spinous processes. FIG. 32 illustrates the medical device in afirst configuration, and FIG. 33 illustrates the medical device in asecond configuration. The medical device 6000 includes an implant 6010and a deployment tool 6020. The implant 6010 includes a distal portion6012, a proximal portion 6014, and a central portion 6016. The implant6010 is configured to be inserted between adjacent spinous processes S.The central portion 6016 is configured to contact and provide a minimumspacing between the spinous processes S when adjacent spinous processesS move toward each other during their range of motion to preventover-extension/compression of the spinous processes S. In someembodiments, the central portion 6016 does not substantially distractthe adjacent spinous processes S. In other embodiments, the centralportion 6016 does distract the adjacent spinous processes S. The implant6010 and the deployment tool 6020 can each be inserted into a patient'sback and moved in between adjacent spinous processes from the side ofthe spinous processes (i.e., a posterior-lateral approach). The use of acurved insertion shaft assists in the use of a lateral approach to thespinous processes S.

The implant 6010 has a collapsed configuration in which the proximalportion 6014, the distal portion 6012 and the central portion 6016 sharea common longitudinal axis. In some embodiments, the proximal portion6014, the distal portion 6012 and the central portion 6016 define a tubehaving a constant inner diameter. In other embodiments, the proximalportion 6014, the distal portion 6012 and the central portion 6016define a tube having a constant outer diameter and/or inner diameter. Inyet other embodiments, the proximal portion 6014, the distal portion6012 and/or the central portion 6016 have different inner diametersand/or outer diameters.

The implant 6010 can be moved from the collapsed configuration to anexpanded configuration, as illustrated in FIG. 33. In the expandedconfiguration, the proximal portion 6014 and the distal portion 6012each have a larger outer perimeter (e.g., outer diameter) than when inthe collapsed configuration, and the proximal portion 6014 and thedistal portion 6012 each have a larger outer perimeter (e.g., outerdiameter) than the central portion 6016. In the expanded configuration,the proximal portion 6014 and the distal portion 6012 are positioned tolimit lateral movement of the implant 6010 with respect to the spinousprocesses S. The proximal portion 6014 and the distal portion 6012 areconfigured to engage the spinous process (i.e., either directly orthrough surrounding tissue and depending upon the relative position ofthe adjacent spinous processes S) in the expanded configuration. Forpurposes of clarity, the tissue surrounding the spinous processes S isnot illustrated.

In some embodiments, the proximal portion 6014, the distal portion 6012and the central portion 6016 are monolithically formed. In otherembodiments, one or more of the proximal portion 6014, the distalportion 6012 and/or the central portion 6016 are separate componentsthat can be coupled together to form the implant 6010. For example, theproximal portion 6014 and distal portion 6012 can be monolithicallyformed and the central portion 6016 can be a separate component that iscoupled thereto. These various portions can be coupled, for example, bya friction fit, welding, adhesive, etc.

The implant 6010 is configured to be coupled to the deployment tool6020. The deployment tool 6020 includes an elongate member 6022 and twoor more engaging portions 6024. In the embodiment shown in FIGS. 32 and33, there are two engaging portions 6024-1 and 6024-2 shown, but itshould be understood that more than two engaging portions 6024 can beincluded. The elongate member 6022 can include a first body portion 6026coupled to a second body portion 6028. In some embodiments, the firstbody portion 6026 is threadedly coupled to the second body portion 6028.The first body portion 6026 and the second body portion 6028 areconfigured to be moved relative to each other. For example, a threadedconnection between the first body portion 6026 and the second bodyportion 6028 can be used to decrease or increase a distance between thefirst body portion 6026 and the second body portion 6028. The first bodyportion 6026 and the second body portion 6028 can be a variety ofdifferent shapes and sizes, and can be the same shape and/or size, orhave a different shape and/or size than each other. For example, in someembodiments, the first body portion includes a straight distal end and astraight proximal end, and the second body portion includes a straightproximal end and a curved or rounded distal end. The curved distal endcan assist with the insertion of the deployment tool into a lumen of animplant and also with the insertion of the medical device into a portionof a patient's body.

The first engaging portion 6024-1 can be coupled to the first bodyportion 6026 and the second engaging portion 6024-2 can be coupled tothe second body portion 6028. The engaging portions 6024 can be, forexample, substantially rectangular, square, circular, oval,semi-circular, or quarter-moon shaped. The engaging portions 6024, canbe spring-loaded devices coupled to the elongate member 6022 of thedeployment tool 6020, such that the engaging portions 6024 are biasedinto a position transverse to a longitudinal axis A defined by theelongate member 6022 and extending from an outer surface of the elongatemember 6022. Upon force exerted on the engaging portions 6024, theengaging portions 6024 can be moved or collapsed to a positionsubstantially below the outer surface of the elongate member 6022. Theengaging portions 6024 can alternatively be coupled to an actuator (notshown) configured to move the engaging portions 6024 from a positiontransverse to the longitudinal axis A and extending from an outersurface of the elongate member 6022, to a position substantially belowthe outer surface of the elongate member 6022.

FIGS. 34-36 illustrate the movement of an engaging portion 6024 as itpasses by a spinous process S when an implant and deployment tool(collectively also referred to as medical device) are coupled togetherand being inserted between adjacent spinous processes. In some cases, asthe medical device is being inserted, an engaging portion 6024 extendingfrom a proximal portion of an implant may come into contact with aspinous process (or other tissue). To allow the engaging portion 6024 topass by the spinous process, the engaging portion 6024 can be moveddownward (as described above) so as to clear the spinous process. FIG.34 illustrates an engaging portion 6024 having a spring-biasedconstruction. The engaging portion 6024 includes a curved portion 6048that initially contacts the spinous process S as the medical device isbeing inserted adjacent a spinous process S. As the curved portion 6048contacts the spinous process S, the engaging portion 6024 is moveddownward at least partially into an interior of the implant 6010, asshown in FIG. 35. The engaging portion 6024 moves back to an extendedposition (e.g., extending transversely from a surface of the implant6010) after the engaging portion clears the spinous process S, as shownin FIG. 36, due to the bias of the spring (not shown).

The deployment tool 6020 can be used to move the implant 6010 from thecollapsed configuration to the expanded configuration, and vice versa,as will be discussed in more detail below. The first body portion 6026and the second body portion 6028 are collectively configured to beinserted at least partially into a lumen (not shown in FIGS. 32 and 33)of the implant 6010, such that at least one engaging portion 6024extends through an opening (not shown in FIGS. 32 and 33) defined by theimplant 6010. The implant 6010 can be configured with one or more suchopenings, each of which is configured to receive an engaging portion6024 disposed on the elongate member 6022 (e.g., the first body portion6026 or the second body portion 6028). The openings defined by theimplant 6010 can be, for example, the openings can be circular, oval,square, rectangular, etc. FIG. 37 illustrates an example of an implant6110 defining curved rectangular openings 6136, and FIG. 47 illustratesan implant 6310 defining curved round or circular openings 6336.

The openings are at least partially defined by an edge (not shown inFIGS. 32 and 33) on the implant 6010. The engaging portions 6024 on thedeployment tool 6020 include a surface (not shown in FIGS. 32 and 33)that is configured to engage or contact the edge of the openings of theimplant 6010 when the elongate member 6022 is inserted into the lumen ofthe implant 6010.

In use, the spinous processes S can be distracted prior to inserting theimplant 6010. When the spinous processes are distracted, a trocar can beused to define an access passage for the implant 6010. In someembodiments, the trocar can be used to define the passage as well asdistract the spinous processes S. Once an access passage is defined, theimplant 6010 can be inserted percutaneously and advanced between thespinous processes, distal end 6012 first, until the central portion 6016is located between the spinous processes S. In some embodiments, theimplant 6010 can be coupled to the deployment tool 6020 prior to beinginserted between the adjacent spinous processes. In other embodiments,the implant 6010 can be inserted between adjacent spinous processeswithout being coupled to the deployment tool 6020. In the latterconfiguration, after the implant 6010 is disposed between the adjacentspinous processes, the deployment tool 6020 can be inserted into thelumen defined by the implant 6010.

Once the implant 6010 is in place between the spinous processes, and thedeployment tool 6020 is in position within the lumen of the implant6010, the implant 6010 can be moved to the second configuration (i.e.,the expanded configuration) by actuating the deployment tool 6020. Forexample, when the deployment tool 6020 is inserted into the lumen of theimplant 6010, the first body portion 6026 is positioned at a firstdistance from the second body portion 6028, and the first engagingportion 6024-1 is positioned at a first distance from the secondengaging portion 6024-2, as shown in FIG. 32. The deployment tool 6020can then be actuated at a proximal end portion (e.g., by turning ahandle) (not shown in FIGS. 32 and 33) causing the threaded couplingbetween the first body portion 6026 and the second body portion 6028 tomove the first body portion 6026 and the second body portion 6028towards each other such that the first body portion 6026 is now at asecond distance (closer) from the second body portion 6028, as shown inFIG. 33. This movement likewise moves the first engaging portion 6024-1and the second engaging portion 6024-2 to a closer position relative toeach other. For example, in FIG. 32, the first engaging portion 6024-1is positioned at a distance from the second engaging portion 6024-2 thatis greater than a distance between the first engaging portion 6024-1 andthe second engaging portion 6024-2 shown in FIG. 33.

As the engaging portions 6024-1 and 6024-2 are moved relative to eachother, the surface (described above and described in more detail below)on the engaging portions 6024 imparts a force on the edge (describedabove and described in more detail below) of the opening defined by theimplant causing the implant to move from the collapsed configuration tothe expanded configuration.

The deployment tool 6020 is configured such that the deployment tool6020 can be removed from the implant 6010 after the implant has beenmoved to the expanded configuration. The implant can remain disposedbetween the spinous processes indefinitely or removed as needed. Forexample, the deployment tool 6020 can be reinserted into the lumen ofthe implant 6010 and actuated in an opposite direction to cause theimplant 6010 to be moved from the expanded configuration back to thecollapsed configuration. In the collapsed configuration, the implant canbe removed from the patient's body or repositioned to a new locationbetween the spinous processes.

In some embodiments, the implant 6010 is inserted percutaneously (i.e.,through an opening in the skin) and in a minimally-invasive manner. Forexample, as discussed in detail herein, the sizes of portions of theimplant are expanded after the implant is inserted between the spinousprocesses. Once expanded, the sizes of the expanded portions of theimplant are greater than the size of the opening. For example, the sizeof the opening/incision in the skin can be between 3 millimeters inlength and 25 millimeters in length across the opening. In someembodiments, the size of the implant in the expanded configuration isbetween 3 and 25 millimeters across the opening.

FIGS. 37-39 illustrate an implant according to an embodiment of theinvention. An implant 6110 includes a proximal portion 6114, a distalportion 6112, and a central portion 6116. The implant 6110 also definesmultiple openings 6132 on an outer surface of the implant 6110. Theopenings 6132 are in communication with a lumen 6158 (shown in FIG. 44)defined by the implant 6110. The openings 6132 are partially defined bya first edge 6136 and a second edge 6138. The implant 6110 includesexpandable portions disposed at the distal portion 6112 and the proximalportion 6114. The expandable portions 6140 can be coupled to the implant6110 or formed integral with the implant 6110, as shown in FIG. 46. Asshown in FIG. 46, elongated slots 6134 can be defined on an outersurface of the implant 6110. The elongated slots 6134 create weakenedareas on the implant 6110 that allow the expandable portions 6140 tofold when exposed to axial force, forming extensions 6142, as shown inFIG. 38.

The implant 6110 can be inserted between adjacent spinous processes (notshown) in a collapsed configuration, as shown in FIG. 37, and then movedto an expanded configuration, as shown in FIG. 38. The implant 6110 canthen be moved back to a collapsed configuration as shown in FIG. 39,which illustrates the expandable portions 6140 in a partially collapsedconfiguration. Although FIG. 39 shows a partially collapsedconfiguration, in some embodiments, the implant can be moved back to thecollapsed configuration as shown in FIG. 37.

To move the implant 6110 from the collapsed configuration to theexpanded configuration, and vice versa, a deployment tool, as describedabove and as shown in FIGS. 40-42, can be used. The deployment tool 6120includes an elongate member 6122 coupled to a handle 6144. The elongatemember 6122 includes a first body portion 6126 coupled to a second bodyportion 6128 through a threaded coupling 6150. A pair of engagingportions 6124-1 are disposed on the first body portion 6126, and a pairof engaging portions 6124-2 are disposed on the second body portion6128. The engaging portions 6124-1 and 6124-2 (also collectivelyreferred to as engaging portions 6124) include a surface 6146 and arounded portion 6148. The threaded coupling 6150 between the first bodyportion 6126 and the second body portion 6128 is used to move the firstbody portion 6126 and the second body portion 6128 such that a distancebetween the first body portion 6126 and the second body portion 6128 ischanged. For example, FIG. 41 illustrates a first distance d−1 betweenthe first body portion 6126 and the second body portion 6128, and FIG.42 illustrates a second distance d−2 between the first body portion 6126and the second body portion 6128. As shown in FIGS. 41 and 42, as thedistance between the first body portion 6126 and the second body portion6128 is changed, a distance between the engaging portions 6124-2 and6124-2 is also changed.

In use, the first body portion 6126 and the second body portion 6128 arecollectively disposed within the lumen 6158 of the implant 6110, suchthat the engaging portions 6124 extend through the openings 6132 andtransverse to an axis B defined by the implant 6110, as shown in FIGS.43-45. In this position, the surface 6146 of the engaging portions 6124is configured to contact the edge 6136 of the openings 6132. FIGS. 43and 44 illustrate the first body portion 6126 and the second bodyportion 6128 disposed within the lumen of the implant 6110, when theimplant is in a collapsed configuration. In this position, the firstbody portion 6126 is at a first distance from the second body portion6128, the engaging portions 6124-1 are at a first distance from theengaging portions 6124-2, and the implant has a first length L−1.

When the implant is positioned between spinous processes S, thedeployment tool 6120 can be actuated to move the implant 6110 to theexpanded configuration, as shown in FIG. 45. When the deployment tool6120 is actuated, the first body portion 6126 is moved closer to thesecond body portion 6128, and the engaging portions 6124-1 are movedcloser to the engaging portions 6124-2. When this occurs, the surface6146 on the engaging portions 6124 impart a force on the edge 6136 ofthe openings 6132, which axially compresses the implant 6110 until theimplant 6110 has a second length L−2, as shown in FIG. 45.

To move the implant 6110 back to the collapsed configuration, thedeployment tool 6120 can be reconfigured such that the surface 6146 ofthe engaging portions 6124 are positioned facing an opposite directionand configured to contact the edge 6138 of the implant 6110, as shown inFIG. 51. In some embodiments, the engaging portions 6124 can be, forexample, removed and re-coupled to the elongate member 6122 (e.g., thefirst body portion 6126 and the second body portion 6128) such that thesame engaging portions 6124 are simply repositioned. In otherembodiments, a second deployment tool can be used having engagingportions positioned in the opposite direction. In either case, thedeployment tool is inserted into the lumen 6158 of the implant 6110 asdone previously, such that the engaging portions 6124 extend through theopenings 6132 of the implant 6110 and the surface 6146 contacts the edge6136 of the implant 6110. The deployment tool 6120 is then actuated inan opposite direction (e.g., turned in an opposite direction) such thatthe first body portion 6126 and the second body portion 6128 arethreadedly moved further away from each other. In doing so, the engagingportions 6124-1 are moved further away from the engaging portions6124-2, and the surface 6146 of the engaging portions 6124 impart aforce on the edge 6138 (instead of edge of 6136) of openings 6132, whichmoves the implant 6110 back to the collapsed or straightenedconfiguration. Thus, the implant described in all of the embodiments ofthe invention can be repeatedly moved between the collapsed and expandedconfigurations as necessary to insert, reposition or remove the implantas desired.

FIG. 48 illustrates a deployment tool according to another embodiment ofthe invention. A deployment tool 6220 includes an elongate member 6222having a first body portion 6226 coupled to a second body portion 6228through a threaded coupling 6250. In this embodiment, the deploymenttool 6220 includes two sets of four (8 total) engaging portions 6224(only six engaging portions are shown in FIG. 48). A first set ofengaging portions 6224-1 are coupled to the first body portion 6226, anda second set of engaging portions 6224-2 are coupled to the second bodyportion 6228. The engaging portions 6224 include a first surface 6246and a second surface 6252. When the deployment tool 6220 is coupled toan implant, the first surface 6246 is configured to contact an edge ofan opening defined on the implant (such as edge 6136 on implant 6110),and the second surface 6252 is configured to contact an opposite edge onthe opening defined by the implant (such as edge 6138 on implant 6110).

Thus, in this embodiment, the deployment tool 6220 can be inserted intoan implant and used to move the implant between a collapsedconfiguration and an expanded configuration without having to repositionthe engaging portions 6224, or use a second deployment tool. To move theimplant from a collapsed configuration to an expanded configuration, thedeployment tool 6220 is actuated in a first direction. To move theimplant back to the collapsed configuration, the deployment tool 6220 isactuated in an opposite direction (e.g., turned in an oppositedirection). When the deployment tool 6220 is actuated to move theimplant from the collapsed configuration to the expanded configuration,the surface 6246 of the engaging portions 6224 impart a force on an edgeof an opening (e.g., edge 6136 on implant 6110), causing the implant tobe axially compressed, as previously described. When the deployment tool6220 is actuated to move the implant from the expanded configuration tothe collapsed configuration, the surface 6252 of the engaging portions6224 imparts a force on an opposite edge of the opening (e.g., edge 6138on implant 6110), causing the implant to be substantially straightenedas previously described.

FIG. 49 illustrates a deployment tool according to another embodiment ofthe invention. A deployment tool 6420 is similar to the deployment tool6220 described above, except in this embodiment, there are only two setsof two engaging portions 6424 (4 total). The engaging portions 6424 aresimilar to the engaging portions 6224 except the engaging portions 6424are substantially rectangular shaped. The engaging portions 6424 includea surface 6446 configured to contact an edge of an opening defined by animplant, and a surface 6452 configured to contact an opposite edge ofthe opening defined by the implant.

FIG. 50 illustrates a deployment tool according to yet anotherembodiment of the invention. A deployment tool 6520 is similarlyconstructed and functions similarly to the previous embodiments. Thedeployment tool 6520 includes an elongate member 6522 that includes afirst body portion 6526 and a second body portion 6528. In thisembodiment, the first body portion 6526 and the second body portion 6528are smaller than illustrated in the previous embodiments, and engagingportions 6524 are coupled to the first body portion 6526 and the secondbody portion 6528 that are more elongate than previously shown.

FIGS. 52 and 53 are schematic illustrations of a deployment tool 11500according to an embodiment of the invention in a first configuration anda second configuration, respectively. The deployment tool 11500 includesan elongate member 11520 and a locking member 11506. The elongate member11520 has a distal end portion 11544 and defines a center line CL. Theelongate member 11520, which can be, for example, a shaft of any typeshown and described above, is configured to engage a spinal implant11100. The locking member 11506 is disposed at the distal end portion11544 of the elongate member 11520 and can be moved relative to theelongate member 11520 between a first position (FIG. 52) and secondposition (FIG. 53) in a direction substantially perpendicular to thecenter line CL, as shown by arrow AA in FIG. 53. Said another way, thelocking member 11506 can translate relative to the elongate member 11520between the first position and the second position in a directionsubstantially perpendicular to the center line CL.

When the locking member 11506 is in the first position, the distal endportion 11544 of the elongate member 11520 can move relative to thespinal implant 11100. When the locking member 11506 is in the secondposition, the distal end portion 11544 of the elongate member 11520 iscoupled to the spinal implant 11100. In this manner, the deployment tool11500 can maintain a position of the spinal implant 11100 such that thespinal implant 11100 can be inserted, removed and/or repositioned withinthe body. In some embodiments, for example, the deployment tool 11500can prevent the spinal implant 11100 from rotating relative to theelongate member 11520 when the locking member 11506 is in the secondposition. In some embodiments, the deployment tool 11500 can prevent thespinal implant 11100 from translating (e.g., moving distally and/orproximally) relative to the elongate member 11520 when the lockingmember 11506 is in the second position.

FIG. 54 shows a deployment tool 12500 according to an embodiment of theinvention. The deployment tool 12500 includes an outer shaft assembly12520 having a proximal shaft 12543 and a distal shaft 12544 joinedtogether by a coupling 12545. The proximal shaft 12543 defines a centerline CL_(P) that is substantially normal to a center line CL_(D) definedby the distal shaft 12544, as shown in FIG. 56. A knob 12515 is disposedat the proximal end portion 12543 of the outer shaft assembly 12520. Aconnector 12505 is disposed at the distal end portion 12544 of the outershaft assembly 12520. As described in more detail herein, the connector12505 is configured to removably connect the distal end portion 12544 ofthe outer shaft assembly 12520 to a spinal implant 6610′ such that thespinal implant 6610′ can be manipulated during insertion into, removalfrom and/or repositioning within the body.

As shown in FIG. 55, the spinal implant 6610′, which is similar to thespinal implant 6610 shown and described above with reference to FIGS.17-23, includes an outer shell 6670′ having a distal portion 6612′ and aproximal portion 6614′. As described above, the outer shell 6670′defines a series of openings and has a series of expandable portionsthat form extensions 6642′ that extend outwardly from the outer shell6670′ when the implant 6610′ is in the expanded configuration. Theproximal end portion 6614′ of the outer shell 6670′ defines threenotches 6606′ that can be used, for example, to align the implant withthe deployment tool 12500, as described above. The outer shell 6670′ ofthe spinal implant 6610′ also defines a series of openings 6607′ thatcan be used to couple the proximal end portion 6614′ of the spinalimplant 6610′ to the deployment tool 12500, as described herein.

The spinal implant 6610′ also includes an inner core 6672′ disposedwithin the outer shell 6670′. As described above, the inner core 6672′is configured to maintain the shape of the implant 6610′ duringinsertion, to prevent the expandable portions from extending inwardlyinto a region inside of the outer shell 6670′ during deployment and/orto maintain the shape of the central portion 6616′ once the implant isin its desired position. The proximal portion of the inner core 6672′defines an opening 6673′ configured to receive a portion of an expansiondevice (also referred to as an insertion tool or a deployment tool),such as expansion device 7500 shown and described above with referenceto FIGS. 24-31.

As shown in FIG. 56, the connector 12505 includes three locking members12506 (only one shown in FIG. 56), such as for example sphericalmembers, an outer sleeve 12590 and an inner sleeve 12580. The lockingmembers 12506 are disposed within openings 12547 defined by the distalshaft 12544 of the outer shaft assembly 12520 (see FIG. 57). Asdescribed herein, the locking members 12506 are configured to movewithin the opening 12547 in a direction substantially perpendicular tothe center line CL_(D) of the distal shaft 12544 of the outer shaftassembly 12520 such that the deployment tool 12500 can be removablycoupled to the spinal implant 6110′. Said another way, the lockingmembers 12506 are configured to translate relative to the distal shaft12544 in a direction substantially perpendicular to the center lineCL_(D) of the distal shaft 12544 of the outer shaft assembly 12520.

The outer sleeve 12590 is slidably disposed about the distal shaft 12544of the outer shaft assembly 12520. The outer sleeve 12590 includes anactuation surface 12591 and a retention surface 12592. The actuationsurface 12591 and/or the retention surface 12592 can be a curved surface(e.g., the surface of a cylinder or cone) or a planar surface. As shownin FIGS. 56 and 61, the actuation surface 12591 is at an acute anglewith respect to the center line CL_(D). The retention surface 12592 issubstantially parallel to the center line CL_(D). The outer sleeve 12590has an extended position (see FIGS. 61 and 62) and a retracted position(see FIG. 56). When the outer sleeve 12590 is in the extended position,the retention surface 12592 engages the locking members 12506 to preventthe locking members 12506 from moving out from the openings 12547. Inthis manner, the retention surface 12592 of the outer sleeve 12590retains the locking members 12506 within the openings 6607′ of thespinal implant 6610′.

As shown in FIG. 56, when the outer sleeve 12590 is in the retractedconfiguration, the actuation surface 12591 engages the locking members12506. When the outer sleeve 12590 moves from the retracted position tothe extended position, as indicated by the arrow BB in FIGS. 56 and 61,the force moving the outer sleeve 12590 is transmitted via the actuationsurface 12591 to the locking members 12506. Because the actuationsurface 12591 is at an acute angle with respect to the center lineCL_(D) (e.g., the direction of motion of the outer sleeve 12590), acomponent of the force transmitted via the actuation surface 12591 tothe locking members 12506 has an inward direction that is substantiallynormal to the center line CL_(D). In this manner, outer sleeve 12590actuates the locking members 12506 inwardly in a direction that issubstantially normal to the center line CL_(D) when the outer sleeve12590 is moved from its retracted position to its extended position.

The outer sleeve 12590 is coupled to the outer shaft assembly 12520 by apin 12549 that extends from the distal shaft 12544 of the outer shaftassembly 12520. A portion of the pin 12549 is received within anelongated opening 12594 (see FIG. 58) defined by the outer sleeve 12590.In use, a portion of the pin 12549 engages the ends of the elongatedopening 12594 to limit the distance through which the outer sleeve 12590can move with respect to the distal shaft 12544 of the outer shaftassembly 12520 when moving between the extended position and theretracted position. Said another way, when the outer sleeve 12590 is inthe retracted position, as shown in FIG. 56, the pin 12549 is in contactwith a distal end of the elongated opening 12594. Similarly, when theouter sleeve is in the extended position, as shown in FIGS. 61 and 62,the pin 12549 is in contact with a proximal end of the elongated opening12594. Accordingly, the distance through which the outer sleeve 12590can move with respect to the outer shaft assembly 12520 is approximatelythe length of the elongated opening 12594 along a direction parallel tothe center line CL_(D).

As described herein, the inner sleeve 12580 cooperates with the outersleeve 12590 to actuate and/or retain the locking members 12506 toremovably couple the deployment tool 12500 to the spinal implant 6110′.The inner sleeve 12580 is slidably disposed within the distal shaft12544 of the outer shaft assembly 12520. As shown in FIG. 59, the innersleeve 12580 includes an outer surface 12586 and an inner surface 12585.The inner surface 12585 of the inner sleeve 12580 includes a flattedsurface 12583 and defines an opening within which a drive member 12532is disposed. Alternatively, the drive member 12532 can be monolithicallyformed with the remaining portions of the inner sleeve 12580. The outersurface 12586 of the inner sleeve 12580 defines a protrusion 12582 and aretention surface 12584. As shown in FIGS. 56 and 57, the protrusion12582 is received within a slot 12556 defined by the distal shaft 12544of the outer shaft assembly 12520 to prevent the inner sleeve 12580 fromrotating relative to the distal shaft 12544 of the outer shaft assembly12520 while allowing the inner sleeve 12580 to move in a directionparallel to the center line CL_(D).

The inner sleeve 12580 has an extended position (see FIG. 56) and aretracted position (see FIGS. 61 and 62). When the inner sleeve 12580 isin the extended position, the retention surface 12584 engages thelocking members 12506 to prevent the locking members 12506 from movinginto the openings 12547. In this manner, the retention surface 12584 ofthe inner sleeve 12580 maintains the position of the locking members12506 outwardly against the retention surface 12592 of the outer sleeve12590, thereby preventing the outer sleeve 12590 from moving from itsretracted position (FIG. 56) to its extended position (FIGS. 61 and 62).Said another way, when the inner sleeve 12580 is in its extendedposition, the outer sleeve 12590 is in its retracted position.Similarly, when the inner sleeve 12580 is in its retracted position, theouter sleeve 12590 can be in its extended position.

As shown in FIGS. 61 and 62, when the inner sleeve 12580 moves from itsextended position to its retracted position as indicated by the arrow CCin FIGS. 56 and 61, the locking members 12506 are disengaged from theretention surface 12584 of the inner sleeve 12580. Accordingly, when theinner sleeve 12580 is in its retracted position the locking members12506 can move inwardly in a direction that is towards and substantiallynormal to the center line CL_(D) within the openings 6607′ of the spinalimplant 6610′.

The outer sleeve 12590 is biased towards its extended position by aspring 12509 disposed between a shoulder surface 12555 of the distalshaft 12544 of the outer shaft assembly 12520 (see FIG. 57) and thespring engagement surface 12593 of the outer sleeve 12590 (see FIG. 56).Similarly, the inner sleeve 12580 is biased towards its extendedposition by a spring 12507 disposed between a surface of a miter gear12565 (shown in FIG. 56) disposed within the outer shaft assembly 12520and the end of the inner sleeve 12580.

The deployment tool 12500 includes an inner shaft assembly 12561 havinga proximal shaft 12562 and a distal shaft 12563. The proximal shaft12562 of the inner shaft assembly 12561 is movably disposed within theproximal shaft 12543 of the outer shaft assembly 12520 such that theproximal shaft 12562 of the inner shaft assembly 12561 is concentricwith the center line CL_(P). Similarly, the distal shaft 12563 of theinner shaft assembly 12561 is movably disposed within the distal shaft12544 of the outer shaft assembly 12520 such that the distal shaft 12563of the inner shaft assembly 12561 is concentric with the center lineCL_(D).

The knob 12515 is coupled to the proximal shaft 12562 of the inner shaftassembly 12561 such that the proximal shaft 12562 of the inner shaftassembly 12561 rotates about the center line CL_(P) as shown by thearrow DD in FIG. 62 when the knob 12515 is rotated. The proximal shaft12562 of the inner shaft assembly 12561 is operatively coupled to thedistal shaft 12563 of the inner shaft assembly 12561 by two miter gears12565. The miter gears 12565 are coupled to the proximal shaft 12562 ofthe inner shaft assembly 12561 and the distal shaft 12563 of the innershaft assembly 12561 by fasteners 12566. The miter gears 12565 areconfigured to rotate with the outer shaft assembly 12520 and aresupported by bearing surfaces 12558 defined by the outer shaft assembly12520. In this manner, when the proximal shaft 12562 of the inner shaftassembly 12561 rotates about the center line CL_(P), the distal shaft12563 of the inner shaft assembly 12561 rotates about the center lineCL_(D), as shown by the arrow EE in FIG. 62.

A drive member 12532 is coupled to the distal shaft 12563 of the innershaft assembly 12561 such that a portion of the drive member 12532 ismovably disposed within at least a portion of the inner sleeve 12580. Asshown in FIGS. 60 and 62, the drive member 12532 includes an end surface12573, an outer surface 12577 and an inner surface 12578. The outersurface 12577 includes a flatted surface 12576 that corresponds to aflatted surface 12583 defined by the inner sleeve 12580. The innersurface 12578 includes a threaded portion 12572 configured to engage thethreaded portion 12571 of the distal shaft 12563 of the inner shaftassembly 12561. In this manner, when the distal shaft 12563 of the innershaft assembly 12561 rotates as shown by the arrow EE in FIG. 62, thedrive member 12532 moves within the outer shaft assembly 12520 as shownby the arrow FF in FIG. 62. Moreover, the corresponding flatted surfaces12583, 12576 prevent the drive member 12532 from rotating within theinner sleeve 12580 and/or the outer shaft assembly 12520.

In some embodiments, the deployment tool 12500 can be used to move thespinal implant 6610′ from an expanded configuration (FIG. 61) to acollapsed configuration (FIG. 62) to facilitate removal and/orrepositioning of the spinal implant 6610′. First, the distal shaft 12544of the outer shaft assembly 12520 is inserted into the body of a patientand coupled to the outer shell 6670′ of the spinal implant 6610′ via theconnector 12505. More particularly, the distal shaft 12544 of the outershaft assembly 12520 is brought into engagement with the proximal endportion 6614′ of the spinal implant 6610′ by moving the distal shaft12544 relative to the spinal implant 6610′ as shown by the arrow GG inFIG. 61. When the distal shaft 12544 of the outer shaft assembly 12520engages the proximal end portion 6614′ of the spinal implant 6610′,continued movement in the direction indicated by arrow GG causes theinner sleeve 12580 to move from its extended position (FIG. 56) to itsretracted position (FIG. 61) along the direction of arrow CC in FIG. 61.

When the proximal end portion 6614′ of the spinal implant 6610′ isreceived within the distal shaft 12544 of the outer shaft assembly12520, the openings 6607′ are aligned with the locking members 12506.Accordingly, because the locking members 12506 are no longer held inplace by the retention surface 12584 of the inner sleeve 12580 and/orthe outer shell 6670′ of the spinal implant 6610′, the locking members12506 are moved inwardly (i.e., towards the center line CL_(D)) by theactuation surface 12591 of the outer sleeve 12590 in a directionsubstantially perpendicular to the center line CL_(D). In this manner,the locking members 12506 are moved inwardly to engage the openings6607′ (e.g., the locking members 12506 can complimentarily fit withinthe openings 6607′). The openings 6607′ are sized such that a portion ofeach of the locking members 12506 remain within the openings 12547defined by the outer shaft assembly 12520 to removably couple the distalshaft 12544 of the outer shaft assembly 12520 to the outer shell 6670′of the spinal implant 6610′.

After the distal shaft 12544 of the outer shaft assembly 12520 iscoupled to the outer shell 6670′ of the spinal implant 6610′, the knob12515 is rotated, thereby causing the inner shaft assembly 12561 torotate as indicated by the arrow EE in FIG. 62. The rotation of theinner shaft assembly 12561 within the drive member 12532 movably engagesthe threaded portions 12571, 12572, thereby causing the drive member12532 to move within the inner sleeve 12580 as indicated by the arrow FFin FIG. 62. As discussed above, the flatted surface 12576 of the drivemember 12532 (see FIG. 60) engages the flatted surface 12583 of theinner sleeve 12580 (see FIG. 59) to prevent the drive member 12532 fromrotating within the inner sleeve 12580. Additionally, the protrusion12582 of the inner sleeve 12580 is received within the slot 12556defined by the distal shaft 12544 of the outer shaft assembly 12520 toprevent the inner sleeve 12580 from rotating relative to the outer shaftassembly 12520.

When the drive member 12532 moves distally, the engagement surface 12573of the drive member 12532 engages the inner core 6672′ of the spinalimplant 6610′. Continued movement of the drive member 12532 as indicatedby the arrow FF in FIG. 62 moves the inner core 6672′ relative to theproximal portion 6614′ of the spinal implant 6610′. In this manner, thespinal implant 6610′ can be moved from its expanded configuration to itscollapsed configuration while disposed within a patient, for example,due to a prior medical procedure in which the spinal implant 6610′ wasimplanted and moved to its expanded configuration.

After the spinal implant 6610′ is removed from and/or repositionedwithin the body, the deployment tool 12500 can be removed from thespinal implant 6610′ by moving the outer sleeve 12590 from its extendedposition to its retracted position by applying a force sufficient toovercome the biasing force from spring 12509. Because the retentionsurface 12592 of the outer sleeve 12590 does not engage the lockingmembers 12506 when the outer sleeve 12590 is in its retracted position,the distal shaft 12544 of the outer shaft assembly 12520 can be movedrelative to the outer shell 6670′ of the spinal implant 6610′.Accordingly, when the distal shaft 12544 of the outer shaft assembly12520 is disengaged from the outer shell 6670′ of the spinal implant6610′, the force from the spring 12507 moves the inner sleeve 12580 fromits retracted position to its extended position, thereby retaining thelocking members 12506 within the opening 12547 of the distal shaft 12544of the outer shaft assembly 12520.

Although the connector 12505 is shown and described in FIGS. 56, 61 and62 as including locking members 12506, in other embodiments, theconnector 12505 can include any suitable locking member. For example, insome embodiments, a locking member can be an engaging portion of thetype shown and described above with reference to FIGS. 34-36. In otherembodiments, a locking member can be a protrusion, a pin and/or aretaining ring.

Similarly, the openings 6607′ defined by the outer shell 6670′ of thespinal implant 6610′ can have any shape suitable to receive andcomplimentarily fit with the locking members 12506. For example, in someembodiments, the openings 6607′ can be elongated about the circumferenceof the outer shell 6670′, which can allow the outer shell 6670′ torotate a predetermined amount with respect to the distal shaft 12544 ofthe outer shaft assembly 12520 when the distal shaft 12544 of the outershaft assembly 12520 is coupled to the outer shell 6670. Similarly, inother embodiments, the openings 6607′ can be elongated about alongitudinal axis of the outer shell 6670′, which can allow the outershell 6670′ to translate a predetermined amount with respect to thedistal shaft 12544 of the outer shaft assembly 12520 when the distalshaft 12544 of the outer shaft assembly 12520 is coupled to the outershell 6670.

Although the angle of the actuation surface 12591 is shown as beingapproximately 45° with respect to the center line CL_(D), in otherembodiments, the actuation surface 12591 can be disposed at any suitableangle with respect to the center line CL_(D). For example, in someembodiments, the angle between the actuation surface 12591 and thecenter line CL_(D) can be between 30° and 60°. In other embodiments, theactuation surface 12591 can include multiple linear and/or curvedportions, each of which is disposed at any suitable angle with respectto the center line CL_(D). In yet other embodiments, the actuationsurface 12591 can be a curved surface.

Although the springs 12507 and 12509 are shown and described above asbeing coil springs, in other embodiments the inner sleeve 12580 and/orthe outer sleeve 12590 can be biased by any suitable biasing member.Such biasing members can include, for example, an elastic member, amagnetic member or the like.

Although the deployment tool 12500 is shown and described above as beingused to move a spinal implant from an expanded configuration to acollapsed configuration, the deployment tool 12500 can also be usedinsert a spinal implant and/or move a spinal implant from a collapsedconfiguration to an expanded configuration.

Although the deployment tool 12500 is shown and described as includingan outer shaft assembly 12520 having a proximal shaft 12543 disposedsubstantially normal to a distal shaft 12544, in other embodiments, adeployment tool can have any suitable shape. For example, in someembodiments, a deployment tool can have a straight outer shaft. In otherembodiments, a deployment tool can have a curved outer shaft. Forexample, in some embodiments, a deployment tool can have an outer shaftthat defines one or more radii of curvature suitable to define and/orproceed along a desired passageway within the body. Such passageways caninclude, for example, a lateral passageway for accessing adjacentspinous processes, a mid-line passageway for accessing adjacent spinousprocesses, or the like. Moreover, the shape of the deployment tool canbe configured such that the spinal implant is aligned as desired duringinsertion, repositioning and/or removal.

Although the deployment tool 12500 is shown and described as including aconnector 12505 and a drive member 12532 configured to move within aspinal implant, in other embodiments a deployment tool can include onlya connector of the types shown and described herein. Similarly, in yetother embodiments a deployment tool can include only a drive memberconfigured to move within a spinal implant.

Although the deployment tool 12500 is shown and described above asincluding a spring-biased actuator (e.g., the outer sleeve 12590) and alocking member 12506 configured to move in a direction substantiallyperpendicular to the center line CL_(D), in other embodiments, adeployment tool can include any suitable actuator and/or a lockingmember configured to move in any suitable direction. For example, FIGS.63 and 64 are schematic illustrations of a deployment tool 13500according to an embodiment of the invention. The deployment tool 13500includes an elongate member 13520, a locking member 13506 and anactuator 13595. The elongate member 13520 has a distal end portion 13544and defines a center line CL. The elongate member 13520, which can be,for example, a shaft of any type shown and described above, isconfigured to engage a spinal implant 13100. The locking member 13506 isdisposed at the distal end portion 13544 of the elongate member 13520and can be moved relative to the elongate member 13520 between a firstconfiguration (FIG. 63) and second configuration (FIG. 64), as shown byarrow HH in FIG. 64, when the distal end portion 13544 of the elongatemember 13520 engages the spinal implant 13100. The locking member 13506can be moved in any suitable direction relative to the center line CL.

When the locking member 13506 is in the first configuration, the distalend portion 13544 of the elongate member 13520 can move relative to thespinal implant 13100. When the locking member 13506 is in the secondconfiguration, the distal end portion 13544 of the elongate member 13520is coupled to the spinal implant 13100. In this manner, the deploymenttool 13500 can maintain its position relative to the spinal implant13100 such that the spinal implant 13100 can be inserted, removed and/orrepositioned within the body by deployment tool 13500.

The actuator 13595 can be any suitable actuator configured to move thelocking member 13506 between the first configuration and the secondconfiguration. In some embodiments, for example, the actuator can be amechanical actuator, a pneumatic actuator, a hydraulic actuator and/oran electronic actuator. Moreover, in some embodiments, the actuator13595 can be configured to retain the locking member 13506 in the firstconfiguration and/or the second configuration. For example, in someembodiments, the actuator 13595 can be a mechanical actuator similar tothe outer sleeve 12590 shown and described above.

Although the deployment tools are shown and described above as includinga locking member configured to move inwardly relative to a spinalimplant to engage the spinal implant, in other embodiments, a deploymenttool can include a locking member configured to move outwardly relativeto a spinal implant. For example, FIGS. 65 and 66 are schematicillustrations of a deployment tool 14500 according to an embodiment ofthe invention in a first configuration and a second configuration,respectively. The deployment tool 14500 includes an elongate member14520 and a locking member 14506. The elongate member 14520 has a distalend portion 14544 configured to be removably disposed within an interiorportion 14158 defined by a spinal implant 14100.

The locking member 14506 is movable between a first configuration and asecond configuration and is configured to releasably couple the distalend portion 14544 of the elongate member 14520 to the spinal implant14100. When the locking member 14506 is in the first position, thelocking member 14506 is disposed substantially within the interiorportion 14158 of the spinal implant 14100 such that the elongate member14520 can move relative to the spinal implant 14100. When the lockingmember 14506 is in the second position, the locking member 14506 engagesa surface 14159 (e.g. a surface defining the interior portion 14158) ofthe spinal implant 14100 such that the elongate member 14520 cannotsubstantially move relative to the spinal implant 14100. In this manner,the deployment tool 14500 can maintain its position relative to thespinal implant 14100 such that the spinal implant 14100 can be inserted,removed and/or repositioned within the body by the deployment tool14500. For example, in some embodiments, the deployment tool can beconfigured to maintain its position relative to a spinal implant tochange the spinal implant from a first configuration (e.g., an expandedconfiguration) to a second configuration (e.g., a retractedconfiguration).

FIG. 67 shows a deployment tool 15500 according to an embodiment of theinvention. The deployment tool 15500 includes a curved outer shaft 15520and a curved inner shaft 15561 (see FIGS. 70-73) movably disposed withinthe outer shaft 15520. The outer shaft 15520 has a proximal end portion15543 and a distal end portion 15544. The distal end portion 15544defines a center line CL_(D) (see FIG. 70). A knob assembly 15515similar to the knob assembly 1515 shown and described above withreference to FIGS. 11-14, is disposed at the proximal end portion 15543of the outer shaft 15520. A connector 15505 is disposed at the distalend portion 15544 of the outer shaft 15520. As described in more detailherein, the connector 15505 is configured to removably connect thedistal end portion 15544 of the outer shaft 15520 to a spinal implant15610 such that the spinal implant 15610 can be moved between anexpanded configuration and a collapsed configuration during removaland/or repositioning within the body.

As shown in FIG. 68, the spinal implant 15610, which is similar to thespinal implants 6610 and 6610′ shown and described above, includes anouter shell 15670 having a distal portion 15612 and a proximal portion15614. The outer shell 15670 defines a series of openings 15618 and hasmultiple expandable portions 15640 that form extensions 15642 thatextend outwardly from the outer shell 15670 (with respect to center lineCL_(D)) when the implant 15610 is in the expanded configuration (seeFIG. 71). The outer shell 15670 also defines an interior portion 15658and a shoulder surface 15678 within the interior portion 15658

The spinal implant 15610 includes an inner core 15672 disposed withinthe interior portion 15658 defined by outer shell 15670. The inner core15672 is fixedly coupled to the distal portion 15612 of the outer shell15670 at an attachment joint 15674. The inner core 15672 can be fixedlycoupled to the outer shell 15670 by any suitable means, such as, forexample, a weld, an adhesive bond, an interference fit or the like. Theproximal portion of the inner core 15672 defines an opening 15673 havinga threaded portion 15676 and defines surface 15677. The threaded portion15676 can be configured, for example, to be coupled to a correspondingthreaded portion an expansion device, such as expansion device 7500shown and described above (e.g., see FIGS. 24-31).

Turning to FIG. 70, the connector 15505 includes three locking members15506 (only one shown in FIG. 70). A portion of each locking member15506 is disposed within a respective opening 15547 defined by thedistal end portion 15544 of the outer shaft 15520. As described herein,the locking members 15506 are configured to move within the openings15547 in directions substantially perpendicular to the center lineCL_(D) of the distal end portion 15544 of the outer shaft 15520 suchthat the deployment tool 15500 can be removably coupled to the spinalimplant 15610.

The inner shaft 15561 is slidably disposable within the outer shaft15520 between a retracted position (see FIGS. 70 and 71) and at leastone expanded position (see e.g., FIGS. 72 and 73). A distal end portion15563 of the inner shaft 15561 includes an actuation surface 15591 thatdefines a recess 15596 within which a portion of each locking member15506 can be received when the inner shaft 15561 is in the retractedposition. The actuation surface 15591 is at an acute angle with respectto the center line CL_(D). The distal end portion 15563 of the innershaft 15561 also includes a retention surface 15592. The retentionsurface 12592 is substantially parallel to the center line CL_(D).

When the inner shaft 15561 is in the retracted configuration, theactuation surface 15591 engages and/or is adjacent the locking members15506. When the inner shaft 15561 moves from the retracted position tothe extended position, as indicated by the arrow II in FIG. 72, theforce moving the inner shaft 15561 is transmitted via the actuationsurface 15591 to the locking members 15506. Because the actuationsurface 15591 is at an acute angle with respect to the center lineCL_(D) (e.g., the direction of motion of the inner shaft 15561), acomponent of the force transmitted via the actuation surface 15591 tothe locking members 15506 has an outward direction that is substantiallynormal to the center line CL_(D). In this manner, inner shaft 15561actuates the locking members 15506 outwardly in a direction that issubstantially normal to the center line CL_(D) when the inner shaft15561 is moved from its retracted position to its extended position.Said another way, movement of the inner shaft 15561 from its retractedposition to its extended position causes the locking members 15506 totranslate relative to the outer shaft 15520 in a direction that issubstantially normal to the center line CL_(D).

When the inner shaft 15561 is in the extended position, the retentionsurface 15592 engages the locking members 15506 to prevent the lockingmembers 15506 from moving inwardly through the opening 15547 (i.e.,towards the center line CL_(D)). In this manner, the retention surface15592 of the inner shaft 15561 retains the locking members 15506 inposition against the shoulder surface 15678 of the spinal implant 15610as shown in FIGS. 72 and 73 and described herein. Conversely, when theinner shaft 15561 is moved from the extended position to the retractedposition, the retention surface 15592 is disengaged from the lockingmembers 15506, thus allowing the locking members 15506 to move inwardlythrough the opening. In this manner, the connector 15505 can bedisconnected from the spinal implant 15610.

In some embodiments, the deployment tool 15500 can be used to move thespinal implant 15610 from an expanded configuration (FIG. 71) to acollapsed configuration (FIG. 73) to facilitate removal and/orrepositioning of the spinal implant 15610. First, the distal end portion15544 of the outer shaft 15520 is inserted into the body and disposedwithin the outer shell 15670 of the spinal implant 15610, as shown inFIG. 71. When the distal end portion 15544 of the outer shaft 15520 isdisposed within the outer shell 15670, the inner shaft 15561 is movedfrom its retracted position to a first extended position, as shown bythe arrow II in FIG. 72. The inner shaft 15561 can be moved, forexample, by rotating the knob assembly 15515 as described above.

As described above, when the inner shaft 15561 is moved distallyrelative to the outer shaft 15520, the actuation surface 15591 urges thelocking members 15506 outwardly through the openings 15547 in adirection substantially perpendicular to the center line CL_(D) and intoengagement with the shoulder surface 15678 (e.g. see the arrow JJ inFIG. 72 for the locking member 15506 shown in FIG. 72). In this manner,the outer shell 15670 of the spinal implant 15610 is prevented frommoving distally relative to the deployment tool 15500.

After the distal end portion 15544 of the outer shaft 15520 is coupledto the outer shell 15670 of the spinal implant 15610, the inner shaft15561 is moved from the first expanded position to a second expandedposition, as shown by the arrow KK in FIG. 73. Accordingly, anengagement surface 15573 of the inner shaft 15561 engages the surface15677 of the inner core 15672 and moves the inner core 15672 distallyrelative to the proximal portion 15614 of the spinal implant 15610. Inthis manner, the spinal implant 15610 can be moved from its expandedconfiguration to its collapsed configuration.

Although the locking members 15506 are shown and described above asengaging the shoulder surface 15678 to prevent distal motion of theouter shell 15670 of the spinal implant 15610 relative to the deploymenttool 15500, in some embodiments, the locking members 15506 cancomplimentarily fit with an opening defined by a surface of an interiorportion of a spinal implant. For example, in some embodiments, aninterior surface of an implant can define a notch, groove, or otherrecessed region within which the locking members can be disposed.

As described above, in some embodiments, a deployment tool can includeany suitable type of connector to releasably couple the deployment toolto a spinal implant and any suitable type of drive member configured tomove within the spinal implant. For example, FIG. 74 is a schematicillustration of a deployment tool 16500 according to an embodiment ofthe invention. The deployment tool 16500 includes a first elongatemember 16520, a second elongate member 16561 and a connector 16505. Theconnector 16505 is disposed at a distal end portion 16544 first of thefirst elongate member 16520. The connector 16505, which can be anysuitable connector as shown and described herein, is configured toreleasably connect the distal end portion 16544 of the first elongatemember 16520 to an outer member 16670 of a spinal implant 16610. Forexample, in some embodiments, the connector 16505 can be configured toprevent the spinal implant 16610 from moving distally relative to thefirst elongate member 16520. Similarly, in some embodiments, theconnector 16505 can be configured to prevent the spinal implant 16610from rotating relative to the first elongate member 16520.

The second elongate member 16561 is movably disposed within the distalend portion 16544 of the first elongate member 16520. In someembodiments, for example, the second elongate member 16561 can translatewithin the distal end portion 16544 of the first elongate member 16520,as shown by the arrow LL in FIG. 74. In other embodiments, the secondelongate member 16561 can rotate within the distal end portion 16544 ofthe first elongate member 16520, as shown by the arrow MM in FIG. 74. Inyet other embodiments, the second elongate member 16561 can translateand rotate within the distal end portion 16544 of the first elongatemember 16520.

The second elongate member 16561 includes a surface 16573 configured toengage an inner member 16672 of the spinal implant 16610. In thismanner, as described above, the deployment tool 16500 can change theconfiguration of the spinal implant 16610 to facilitate the insertion,removal and/or repositioning of the spinal implant 16610 within thebody.

FIGS. 75-81 show a deployment tool 17500 according to an embodiment ofthe invention. The deployment tool 17500 includes an outer shaft 17520and an inner shaft 17561 movably disposed within the outer shaft 17520.The deployment tool 17500 also includes a connector 17505 disposed at adistal end portion 17544 of the outer shaft 17520. As described in moredetail herein, the connector 17505 is configured to releasably connectthe distal end portion 17544 of the outer shaft 17520 to a spinalimplant 17610 (not shown in FIGS. 75 and 76) such that the spinalimplant 17610 can be moved between an expanded configuration and acollapsed configuration during removal and/or repositioning within thebody.

The connector 17505 includes three tines 17506 that extendlongitudinally from the distal end portion 17544 of the outer shaft17520. As shown in FIGS. 75 and 76, the tines 17506 are L-shaped andterminate in end portions 17559 that are substantially normal to acenter line CL_(D) of the distal end portion 17544 of the outer shaft17520. As shown in FIG. 76 (the outer shaft 17520 is shown without theinner shaft 17561 for clarity), the tines 17506 define a diameter D1that is no less than a diameter D2 of the receiving area 17542 definedby the connector 17505 and/or the outer shaft 17520. In this manner, thespinal implant 17610 can be received within the receiving are 17542without being obstructed by the tines 17506.

In some embodiments, the deployment tool 17500 can be used to move thespinal implant 17610 from an expanded configuration (FIG. 80) to acollapsed configuration (FIG. 81) to facilitate removal and/orrepositioning of the spinal implant 17610. First, the distal end portion17544 of the outer shaft 17520 is inserted into the body and disposedabout the spinal implant 17610 such that a proximal portion 17614 of anouter shell 17670 of the spinal implant 17610 is received within thereceiving area 17542, as shown by the arrow NN in FIG. 77. The connector17505 is then positioned such that the end portions 17559 of the tines17506, at least in part, are disposed within and aligned with theopenings 17643 formed by the retention members 17642 of the spinalimplant 176100. In some embodiments, the surface defining the receivingarea 17542 can include a protrusion to limit the range of travel of thespinal implant 17610 within the receiving area 17542 to ensure that thetines 17506 are aligned with the openings 17643.

When the distal end portion 17544 of the outer shaft 17520 is disposedabout the spinal implant 17610, the connector 17505 is rotated about thecenter line CL_(D) of the distal end portion 17544 of the outer shaft17520, as shown by the arrow OO in FIG. 78. In this manner, the endportions 17559 of the tines 17506 are received within the openings 17643formed by the retention members 17642 of the spinal implant 176100 toreleasably couple the distal end portion 17544 of the outer shaft 17520to the outer shell 17670 of the spinal implant 17610.

The connector 17505 can be rotated about the center line CL_(D) in anysuitable manner. For example, the connector 17505 can be fixedly coupledto the outer shaft 17520 and the connector 17505 can be rotated byrotating the outer shaft 17520. In such an embodiment, the connector17505 can be monolithically formed with the outer shaft 17520. In otherembodiments, however, the connector can be rotatably coupled to thedistal end of the outer shaft. In such embodiments, for example, theconnector can be rotated relative to the outer shaft by an actuatordisposed at the distal end portion of the outer shaft, as describedabove. In other embodiments, the connector can be rotated by rotating aknob assembly disposed at a proximal end portion of the outer shaft, asshown and described above.

The inner shaft 17561 is then moved within the outer shaft 17520 betweena retracted position (see FIG. 77) and at least one expanded position(see FIG. 81). A distal end portion 17563 of the inner shaft 17561includes an engagement surface 15573 of the inner shaft 17561 engagesthe inner core 17672 and moves the inner core 17672 distally relative tothe proximal portion 17614 of the spinal implant 17610, as shown by thearrow PP in FIG. 81. In this manner, the outer shell 17670 of the spinalimplant 17610 is deformed to move the spinal implant 17610 from itsexpanded configuration to its collapsed configuration.

Although the tines 17506 are shown and described above as engaging aretention member 17642 of a spinal implant 17610, in some embodiments, aconnector can include tines configured to engage any portion of a spinalimplant, for example, portions of the spinal implant configured toreceive the tines of the connector.

Although inner shaft 17561 is shown as translating within the outershaft 17520, in some embodiments, an inner shaft can rotate within anouter shaft to engage a portion of a spinal implant. For example, insome embodiments, an inner shaft can include a rotating portion and adriver, as shown and described above. Similarly, in some embodiments, aninner shaft can include a threaded portion configured to threadablyengage a portion of a spinal implant.

Although the deployment tools shown and described above are configuredto move a spinal implant from an expanded configuration to a retractedconfiguration by plastically deforming a portion of the implant (e.g., aretention member), in some embodiments, a deployment tool can beconfigured to move a spinal implant from an expanded configuration to aretracted configuration by cutting a portion of the spinal implant. Forexample, FIGS. 82 and 83 are front view schematic illustrations of amedical device 18500 according to an embodiment of the invention in afirst position and a second position, respectively. The medical device18500 includes an elongate member 18520 having a distal end portion18544 and defining a center line CL. A cutting edge 18564 is disposed atthe distal end portion 18544 of the elongate member 18520. When theelongate member 18520 moves relative to a spinal implant 18610, as shownby the arrow QQ in FIG. 83, the cutting edge 18564 cuts a portion 18642of the spinal implant 18610. In this manner, the medical device 18500can move the spinal implant 18610 between a first configuration and asecond configuration to facilitate insertion, removal and/orrepositioning the spinal implant within the body.

The spinal implant portion 18642 can be any suitable portion of thespinal implant 18610. For example, in some embodiments, the spinalimplant portion 18642 can be a portion of an outer shell of a spinalimplant. In other embodiments, the spinal implant portion 18642 can be aportion of an inner core of a spinal implant. In yet other embodiments,the spinal implant portion 18642 can be a retention portion of a spinalimplant, such as, for example, an extension portion, a tether, aninflatable retention portion or the like.

Although the elongate member 18520 is shown as moving in a directionparallel to the center line CL, in other embodiments, the elongatemember 18520 can move in any suitable direction. Moreover, in someembodiments, the movement of the elongate member 18520 can betranslation motion, rotation motion and or reciprocation.

As shown in FIG. 84, which shows a top view schematic of the elongatemember 18520 in the second configuration, the cutting edge 18564 islinear and forms an acute angle E) with the center line CL. In thismanner, only a portion of the cutting edge 18564 engages the spinalimplant 18610 when the elongate member 18520 moves. Although the cuttingedge 18564 is shown as being linear, in other embodiments, a cuttingedge can be curved. In yet other embodiments, a cutting edge can bediscontinuous. For example, in some embodiments, an elongate member caninclude multiple cutting edges arranged discontinuously (e.g., asaw-tooth arrangement).

In other embodiments, an elongate member can include multiple cuttingedges that are offset from each other longitudinally along the centerline CL. For example, in some embodiments an elongate member can includea first cutting edge extending a first longitudinal distance from thedistal end portion of the elongate member, a second cutting edgeextending a second longitudinal distance from the distal end portion ofthe elongate member and a third cutting edge extending a thirdlongitudinal distance from the distal end portion of the elongate. Inthis manner, when the elongate member is moved into engagement with thespinal implant, the first cutting edge can engage a first retentionmember of the spinal implant before the second cutting edge and thethird cutting edge engage the spinal implant.

In some embodiments, an elongate member can be configured to receive aportion of a spinal implant such that the cutting edge can be aligned.For example, FIGS. 85-87 show a medical device 19500 according to anembodiment of the invention in a first configuration, a secondconfiguration and a third configuration, respectively. In someembodiments, the medical device 19500 can be used to remove a spinalimplant 19610 from between a pair of adjacent spinous processes SP. Themedical device 19500 includes a shaft 19520, a rod 19570 disposed withinthe shaft 19520, and a spacer 19532. The shaft 19520 includes an implantsupport portion 19530 disposed at a distal end portion 19544 of theshaft 19520. The implant support portion 19530 includes a side wall19540 that defines a receiving area 19542 configured to receive aportion of the spacer 19532. The side wall 19540 also includes a cuttingedge 19564.

First, the distal end portion 19544 of the shaft 19520 is inserted intothe body and disposed such that the spacer 19532 is received within thespinal implant 19610, as shown in FIG. 85. The distal end portion 19544is moved distally as shown by the arrow RR in FIG. 85 such that aproximal end 19614 of the implant is received within a recess 19534defined by the side wall 19540 and the outer surface of the spacer19532. In this manner, the spinal implant 19610 is aligned with respectto the medical device 19500.

The distal end 19563 of the rod 19570 is then threadedly coupled to thedistal end 19612 of the spinal implant 19610 by rotating the rod 19570within the shaft 19520. The rod 19570 can be rotated within the shaft19520 by a knob assembly (not shown in FIGS. 85-87) similar to the knobassembly 1515 shown and described above.

The rod 19570 is then moved proximally within the shaft 19520 as shownby the arrow SS in FIG. 86, which moves the retention members 19642 ofthe spinal implant 19610 into engagement with the cutting edge 19564(e.g., two retention members 19642 shown in FIGS. 85-87). As the rod19570 continues to move proximally, the cutting edges 19564 cut througha portion of the retention members. As shown in FIGS. 85 and 86, whenthe spacer 19532 engages the side wall 19540 defining the receiving area19542, the retention member 19642 is prevented from moving relative tothe cutting edge 19564. In this manner, the medical device 19500 isconfigured to cut only a portion of the retention members 19542,therefore preventing the retention members 19542 from being completelysevered from the spinal implant 19610.

After the retention members 19642 are cut, the shaft 19520 is moveddistally within the body as shown by the arrow TT in FIG. 87.Accordingly, the retention members are bent inwardly towards the implantcenter line, as shown by the arrow UU in FIG. 87, when the spinalimplant 19610 moves past the spinous processes SP.

Although not shown in FIGS. 86-88, the rod 19570 can be rotated and/ortranslated within the shaft 19520 by a knob assembly of the type shownand described above.

Although the cutting edges are shown and described above as beingmonolithically formed with an elongate member, in other embodiments, amedical device can include a cutting member that is formed separatelyfrom the elongate member. In such embodiments, for example, the cuttingmember can include one or more cutting edges and can be coupled to adistal end portion of the elongate member. In some embodiments, acutting member can be fixedly coupled to a distal end portion of anelongate member. In other embodiments, a cutting member can be movablycoupled to a distal end portion of an elongate. In some embodiments, forexample, a medical device can include an elongate member, a cuttingmember disposed at a distal end portion of the elongate member, and anactuator configured to move the cutting member relative to the elongatemember. In such embodiments, the actuator can be an actuator of thetypes shown and described above, such as, for example, a mechanicalactuator (e.g., cable driven, spring driven or the like), a hydraulicactuator, a pneumatic actuator and/or an electronic actuator. In suchembodiments, the cutting member can be moved relative to a spinalimplant without moving the elongate member.

FIG. 88 is a schematic illustration of a medical device 20500 accordingto an embodiment of the invention. The medical device 20500 includes anelongate member 20520 having a distal end portion 20544 and defining acenter line CL. The distal end portion 20544 of the elongate member20520 has cutting portion (e.g., a cutting edge) 20564 and a protrusion20567. When the elongate member 20520 moves relative to a spinal implant20610, as shown by the arrow VV, the cutting edge 20564 cuts a portion20642 of the spinal implant 20610. Additionally, after the cutting edge20564 has cut the portion 20642, the protrusion 20567 moves the portion20642 relative to the spinal implant 20610, as shown by the arrow WW. Inthis manner, the cutting edge 20564 and the protrusion 20567cooperatively cut and bend the portion 20642 of the spinal implant20610, thereby facilitating the insertion, removal and/or repositioningof the spinal implant 20610 within the body.

FIG. 89 is a flow chart illustrating a method according to an embodimentof the invention. A method includes at 6060, percutaneously disposing anexpandable member at a first location between adjacent spinous processeswithin a body of a patient while the expandable member is in a collapsedconfiguration. The expandable member is coupled to a deployment toolthat includes an engaging portion configured to be received through anopening defined by the expandable member. In other embodiments, thedeployment tool can be coupled to the implant after the implant has beendisposed between the spinous processes. After the implant has beendisposed between the adjacent spinous processes, the expandable membercan be moved from the collapsed configuration to an expandedconfiguration at 6062. To do this, the deployment tool can be actuatedwhile the expandable member is disposed between the adjacent spinousprocesses such that the engaging portion of the deployment tool impartsa force to a first location on the expandable member and causes theexpandable member to move from the collapsed configuration to anexpanded configuration. After actuating the deployment tool such thatthe expandable member is moved from the collapsed configuration to theexpanded configuration, the deployment tool can optionally be removedfrom the expandable member, at 6064. In embodiments where the deploymenttool has been removed, the deployment tool can be subsequentlyreinserted into the expandable member.

At 6066, the deployment tool can be actuated again such that theengaging portion imparts a force to a second location on the expandablemember different from the first location on the expandable member, andthe implant is moved from the expanded configuration to the collapsedconfiguration.

After actuating the deployment tool such that the expandable member ismoved from the expanded configuration to the collapsed configuration,the expandable member can optionally be disposed at a second locationbetween the adjacent spinous processes different from the firstlocation, at 6068. In some embodiments, after the deployment tool isactuated such that the expandable member is moved from the expandedconfiguration to the collapsed configuration, the expandable member canoptionally be disposed at a second location outside of the body of thepatient, at 6070.

FIG. 90 is a flow chart illustrating a method 21100 according to anembodiment of the invention. The method 21100 includes inserting anelongate member of a deployment tool having a centerline into a body,21102. The elongate member can be any suitable elongate member of thetypes shown and described above. The elongate member includes a lockingmember disposed at a distal end portion thereof. In some embodiments,the elongate member can be inserted percutaneously. For example, in someembodiments, the elongate member can be inserted percutaneously via alateral incision. In other embodiments, the elongate member can beinserted via a mid-line incision.

A distal end portion of the elongate member is then moved intoengagement with a spinal implant disposed within the body, 21104. Thespinal implant can be any suitable spinal implant as shown and describedabove. In some embodiments, the distal end portion of elongate membercan disposed about a portion of the spinal implant. In otherembodiments, the distal end portion of elongate member can receivedwithin an interior portion of the spinal implant.

The locking member is then moved relative to the elongate member betweena first position and a second position, in a direction substantiallyperpendicular to a center line of the elongate member, 21106. In thismanner, the distal end portion of the elongate member is coupled to thespinal implant. In some embodiments, the locking member can be extendedwithin an opening defined by the elongate member such that a portion ofthe locking member is outside of the opening. The portion fits within anopening defined by the spinal implant to couple the elongate member tothe spinal implant.

In some embodiments, the method 21100 can optionally include moving asleeve disposed about an outer surface of the elongate member such thatthe locking member is retained within the opening defined by the spinalimplant. In other embodiments, the method 21100 can optionally includemoving the elongate member after the elongate member is coupled to thespinal implant such that the spinal implant is removed from the body. Inyet other embodiments, the method 21100 can optionally include changingthe spinal implant from a first configuration to a second configurationafter the elongate member is coupled to the spinal implant, tofacilitate removal of the spinal implant from the body and/orrepositioning of the spinal implant within the body.

FIG. 91 is a flow chart illustrating a method 21200 according to anembodiment of the invention. The method 21200 includes inserting anelongate member of a deployment tool into a body, 21202. The elongatemember can be any suitable elongate member of the types shown anddescribed above. In some embodiments, the elongate member can beinserted percutaneously. For example, in some embodiments, the elongatemember can be inserted percutaneously via a lateral incision. In otherembodiments, the elongate member can be inserted via a mid-lineincision.

A distal end portion of the elongate member is then coupled to an outermember of a spinal implant disposed within the body, 22104. The spinalimplant can be any suitable spinal implant as shown and described above.In some embodiments, for example, the elongate member includes multipletines extending from the distal end portion, each of which areconfigured to be received within an opening defined by the outer portionof the spinal implant. In such embodiments, the distal portion of theelongate member can be coupled to the outer member of the spinal implantby disposing the tines within the openings defined by the outer memberof the spinal implant. In some embodiments, the distal portion of theelongate member can be coupled to the outer member of the spinal implantsuch that the outer member of the implant is prevented from movingdistally relative to the first elongate member.

An inner member of the spinal implant is then moved relative to theouter member of the spinal implant after the elongate member is coupledto the outer member of the spinal implant coupling, 21206. In someembodiments, for example, the elongate member can be a first elongatemember of the deployment tool and the inner member of the spinal implantcan be moved by moving a second elongate member of the deployment toolwithin the first elongate member. The second elongate member isconfigured to engage the inner member of the spinal implant such thatthe inner member of the spinal implant is moved distally relative to theouter member of the spinal implant when the second elongate member ismoved within the first elongate member. In this manner, for example, thespinal implant can be plastically deformed and/or moved from a firstconfiguration to a second configuration.

The second elongate member of the deployment tool can be, for example, adrive member, a shaft or a rod of the types shown and described above.The second elongate member can be moved within the first elongate memberby any suitable manner. For example, in some embodiments, the secondelongate member can be translated and/or rotated within the firstelongate member by a knob assembly disposed at a proximal end portion ofthe first elongate member, as shown and described above.

In some embodiments, the method 21200 can optionally include moving thespinal implant within the body and/or removing the spinal implant fromthe body after the inner member of the spinal implant has been moved.

FIG. 92 is a flow chart illustrating a method 21300 according to anembodiment of the invention. The method 21300 includes coupling a distalend of an elongate member to a spinal implant within a body, 21302. Theelongate member can be any suitable elongate member of the types shownand described above. In some embodiments, the method can optionallyinclude inserting percutaneously the elongate member. For example, insome embodiments, the elongate member can be inserted percutaneously viaa lateral incision. In other embodiments, the elongate member can beinserted via a mid-line incision.

In some embodiments, the elongate member is a first elongate memberwithin which a second elongate member is disposed. In such embodiments,the first elongate member can be coupled to the spinal implant byremovably coupling the second elongate member to the spinal implant. Insome embodiments, for example, the second elongate member can be athreaded rod configured to complimentarily fit within a threaded openingof the spinal implant.

A portion of the spinal implant is then cut with a cutting edge disposedat the distal end portion of the elongate member, 21304. In someembodiments, for example, the cutting edge can be moved relative to theelongate member such that the portion of the spinal implant is cut. Insome embodiments, a retention member of the spinal implant can be cutwith the cutting edge.

In some embodiments, the elongate member is a first elongate memberwithin which a second elongate member is disposed. In such embodiments,the first elongate member can be coupled to the spinal implant byremovably coupling the second elongate member to the spinal implant.Moreover, the cutting edge can be moved relative to the portion of thespinal implant by moving the second elongate member within the firstelongate member.

In some embodiments, the method 21300 can optionally include deformingthe portion of the spinal implant (either plastically or elastically)after the portion of the spinal implant has been cut. In someembodiments, the method 21300 can optionally include removing the spinalimplant from the body after the portion of the spinal implant has beencut.

The various implants and deployment tools described herein can beconstructed with various biocompatible materials such as, for example,titanium, titanium alloyed, surgical steel, biocompatible metal alloys,stainless steel, plastic, polyetheretherketone (PEEK), carbon fiber,ultra-high molecular weight (UHMW) polyethylene, biocompatible polymericmaterials, etc. The material of a central portion of the implant canhave, for example, a compressive strength similar to or higher than thatof bone. In one embodiment, the central portion of the implant, which isplaced between the two adjacent spinous processes, is configured with amaterial having an elastic modulus higher than the elastic modulus ofthe bone, which forms the spinous processes. In another embodiment, thecentral portion of the implant is configured with a material having ahigher elastic modulus than the materials used to configure the distaland proximal portions of the implant. For example, the central portionof the implant may have an elastic modulus higher than bone, while theproximal and distal portions have a lower elastic modulus than bone. Inyet another embodiment, where the implant is configured with an outershell and an inner core. The outer shell can be configured with materialhaving a higher elastic modulus than the inner core (e.g., outer shellis made with titanium alloyed, while the inner core is made with apolymeric material). Alternatively, the outer shell can be configuredwith a material having a lower elastic modulus than the inner core(e.g., the outer shell is made with a polymeric material while the innercore is made with a titanium alloyed material).

While various embodiments of the invention have been described above, itshould be understood that they have been presented by way of exampleonly, and not limitation. Where methods and steps described aboveindicate certain events occurring in certain order, those of ordinaryskill in the art having the benefit of this disclosure would recognizethat the ordering of certain steps may be modified and that suchmodifications are in accordance with the variations of the invention.Additionally, certain of the steps may be performed concurrently in aparallel process when possible, as well as performed sequentially asdescribed above. Thus, the breadth and scope of the invention should notbe limited by any of the above-described embodiments, but should bedefined only in accordance with the following claims and theirequivalents. While the invention has been particularly shown anddescribed with reference to specific embodiments thereof, it will beunderstood that various changes in form and details may be made.

For example, although the embodiments above are primarily described asbeing spinal implants configured to be positioned between adjacentspinous processes, in alternative embodiments, the implants areconfigured to be positioned adjacent any bone, tissue or other bodilystructure where it is desirable to maintain spacing while preventingaxial or longitudinal movement of the implant.

Although the medical devices are shown and described as including animplant and/or a deployment tool, in some embodiments a kit can includeany number of implants and/or any number of deployment tools asdescribed above. For example, a kit can include an implant and twodeployment tools, one deployment tool configured to be used to move theimplant from a collapsed configuration to an expanded configuration, andanother deployment tool configured to be used to move the implant fromthe expanded configuration to the collapsed configuration.Alternatively, a kit can include a single deployment tool have multipleengaging portions as described herein, that can be releasably coupled toan elongate member of a deployment tool. For example, one type or styleof engaging portion can be used to move the implant from a collapsedconfiguration to an expanded configuration, and another type or style ofengaging portion can be used to move the implant from the expandedconfiguration to the collapsed configuration. The kit can includeengaging portions having one of a variety of different shapes and sizes,such that a user can select a particular engaging portion(s) for use ina particular application.

Similarly, although various embodiments have been described as havingparticular features and/or combinations of components, other embodimentsare possible having a combination of any features and/or components fromany of embodiments as discussed above. For example, one such embodimentincludes an elongate member having multiple tines extending from adistal end thereof, the tines configured to be received within a portionof a spinal implant, similar to the deployment tool 17500 shown anddescribed above. The embodiment further includes a spring-biased outersleeve configured to retain the tines within the spinal implant, similarto the sleeves shown in the deployment tool 12500 shown and describedabove.

Similarly, in some embodiments, a deployment tool, an expansion deviceand/or an insertion tool can be configured to perform any combination offunctions described herein. For example, in some embodiments, adeployment tool, an expansion devices and/or an insertion tool can beconfigured to insert a spinal implant into a body, move a spinal implantbetween a retracted configuration and an expanded configuration within abody, reposition a spinal implant within the body and/or remove a spinalimplant within the body. In some embodiments, a deployment tool, anexpansion device and/or an insertion tool can be configured to performonly a single function, such as, for example, removing a spinal implantfrom body. In other embodiments, a kit can include a deployment tool, anexpansion device and/or an insertion tool along with various implementsso that the deployment tool, expansion device and/or insertion tool canbe re-configured to perform any combination of functions describedherein.

1. A method for moving an implant from an expanded configuration to aretracted configuration, comprising: coupling a distal end portion of anelongate body to an implant when the implant is already in the expandedconfiguration and disposed within a patient's body, the distal endportion of the elongate body comprising a cutting edge; cutting aportion of the implant with the cutting edge to form a cut in theimplant; changing the implant from the expanded configuration to theretracted configuration by deforming the implant proximate the cut. 2.The method of claim 1 wherein the implant is disposed within the bodybetween adjacent spinous processes.
 3. The method of claim 1 furthercomprising inserting percutaneously the elongate member into the bodybefore the coupling.
 4. The method of claim 1 wherein: the elongate bodyincludes first and second elongate members, the second elongate memberbeing disposed within the first elongate member; the coupling includesremovably coupling the second elongate member to the implant.
 5. Themethod of claim 4 wherein an implant support portion is disposed at adistal end of the first elongate member and the second elongate memberextends through the first elongate member and the implant supportportion and wherein coupling a distal end of the elongate body to theimplant includes: receiving the implant in a recess formed in theimplant support portion; coupling a distal end of the second elongatemember to a distal end of the implant.
 6. The method of claim 1 wherein:the elongate body includes first and second elongate members, the secondelongate member being disposed within the first elongate member; thecoupling includes removably coupling a distal end portion of the secondelongate member to the implant; the cutting includes moving the secondelongate member in a proximal direction within the first elongatemember, while the second elongate member is coupled to the implant, suchthat the cutting edge engages the portion of the implant.
 7. The methodof claim 6 wherein the cutting includes cutting a portion of a retentionmember of the implant and wherein changing the implant further comprisesmoving the implant in a distal direction past the spinous processes suchthat as the retention member passes the spinous processes, the retentionmember bends inwardly towards a center line of the implant.
 8. Themethod of claim 1 wherein the cutting includes cutting a retentionmember of the implant.
 9. The method of claim 1 wherein: the implantincludes an outer member having a tubular body and an inner memberhaving a cylindrical body, the inner member being disposed within thetubular body of the outer member; the cutting includes cutting a portionof the outer member of the implant.
 10. The method of claim 1 whereinthe cutting includes moving the cutting edge relative to the elongatebody such that the portion of the implant is cut.
 11. The method ofclaim 1 further comprising removing the implant from the body after thecutting.
 12. The method of claim 1 wherein: the implant includes anouter member having a tubular body and an inner member having acylindrical body, the inner member being disposed within the tubularmember; the cutting includes cutting a portion of the inner member ofthe implant.